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<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Mater.</journal-id>
<journal-title>Frontiers in Materials</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Mater.</abbrev-journal-title>
<issn pub-type="epub">2296-8016</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fmats.2015.00058</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Materials</subject>
<subj-group>
<subject>Review</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Recent Progress in the Growth and Applications of Graphene as a Smart Material: A Review</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes">
<name><surname>A&#x000EF;ssa</surname> <given-names>Brahim</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
<xref ref-type="corresp" rid="cor1">&#x0002A;</xref>
<uri xlink:href="http://frontiersin.org/people/u/125928"/>
</contrib>
<contrib contrib-type="author">
<name><surname>Memon</surname> <given-names>Nasir K.</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<uri xlink:href="http://frontiersin.org/people/u/200721"/>
</contrib>
<contrib contrib-type="author">
<name><surname>Ali</surname> <given-names>Adnan</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<uri xlink:href="http://frontiersin.org/people/u/200486"/>
</contrib>
<contrib contrib-type="author">
<name><surname>Khraisheh</surname> <given-names>Marwan K.</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<uri xlink:href="http://frontiersin.org/people/u/258758"/>
</contrib>
</contrib-group>
<aff id="aff1"><sup>1</sup><institution>Qatar Environment and Energy Research Institute (QEERI), Qatar Foundation</institution>, <addr-line>Doha</addr-line>, <country>Qatar</country></aff>
<aff id="aff2"><sup>2</sup><institution>Department of Smart Materials and Sensors for Space Missions, MPB Technologies Inc.</institution>, <addr-line>Montreal, QC</addr-line>, <country>Canada</country></aff>
<author-notes>
<fn fn-type="edited-by"><p>Edited by: Maenghyo Cho, Seoul National University, South Korea</p></fn>
<fn fn-type="edited-by"><p>Reviewed by: Jianbo Yin, Northwestern Polytechnical University, China; Joo-Hyung Kim, Inha University, South Korea</p></fn>
<corresp content-type="corresp" id="cor1">&#x0002A;Correspondence: Brahim A&#x000EF;ssa, Department of Smart Materials and Sensors for Space Missions, MPB Technologies Inc., 151 Hymus Boulevard, Pointe-Claire, Montreal, QC H9R1E9, Canada, <email>baissa&#x00040;qf.org.qa</email></corresp>
<fn fn-type="other" id="fn001"><p>Specialty section: This article was submitted to Smart Materials, a section of the journal Frontiers in Materials</p></fn>
</author-notes>
<pub-date pub-type="epub">
<day>22</day>
<month>09</month>
<year>2015</year>
</pub-date>
<pub-date pub-type="collection">
<year>2015</year>
</pub-date>
<volume>2</volume>
<elocation-id>58</elocation-id>
<history>
<date date-type="received">
<day>06</day>
<month>05</month>
<year>2015</year>
</date>
<date date-type="accepted">
<day>31</day>
<month>07</month>
<year>2015</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#x000A9; 2015 A&#x000EF;ssa, Memon, Ali and Khraisheh.</copyright-statement>
<copyright-year>2015</copyright-year>
<copyright-holder>A&#x000EF;ssa, Memon, Ali and Khraisheh</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/"><p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p></license>
</permissions>
<abstract>
<p>Innovative breakthroughs in fundamental research and industrial applications of graphene material have made its mass and low-cost production as a necessary step toward its real world applications. This one-atom thick crystal of carbon, gathers a set of unique physico-chemical properties, ranging from its extreme mechanical behavior to its exceptional electrical and thermal conductivities, which are making graphene as a serious alternative to replace many conventional materials for various applications. In this review paper, we highlight the most important experimental results on the synthesis of graphene material, its emerging properties with reference to its smart applications. We discuss the possibility to successfully integrating graphene directly into device, enabling thereby the realization of a wide range of applications, including actuation, photovoltaic, thermoelectricity, shape memory, self-healing, electrorheology, and space missions. The future outlook of graphene is also considered and discussed.</p>
</abstract>
<kwd-group>
<kwd>gas-phase growth</kwd>
<kwd>graphene material</kwd>
<kwd>smart applications</kwd>
</kwd-group>
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<fig-count count="16"/>
<table-count count="0"/>
<equation-count count="1"/>
<ref-count count="188"/>
<page-count count="19"/>
<word-count count="14026"/>
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</front>
<body>
<sec id="S1" sec-type="introduction">
<title>Introduction</title>
<p>Graphene material is considered as the first lab-made 2D atomic crystal. Because of their unique physical and chemical properties&#x02009;&#x02013;&#x02009;such as mechanical stiffness, strength and elasticity, and extremely high electrical and thermal conductivity (Geim and Novoselov, <xref ref-type="bibr" rid="B41">2007a</xref>; Geim, <xref ref-type="bibr" rid="B40">2009</xref>)&#x02009;&#x02013;&#x02009;graphene is described to be a serious alternative to replace many conventional materials in various applications, and could enable many disruptive innovation and potentially existing markets. For example, the combination of optical transparency, electrical and thermal conductivities, and mechanical elasticity will find application either in flexible electronics and/or transparent coatings, and the list of such combinations is continuously growing (Figure <xref ref-type="fig" rid="F1">1</xref>). Basically, graphene is a single 2D layer of carbon atoms, with a typical thickness of 0.34&#x02009;nm. It is sp<sup>2</sup> hybridized, where carbon atoms are covalently bonded to three other atoms in a hexagonal lattice structure (Geim, <xref ref-type="bibr" rid="B40">2009</xref>; Layek and Nandi, <xref ref-type="bibr" rid="B82">2013</xref>). Recently, graphene has been extensively investigated, both in terms of fundamental research and R&#x00026;D applications. Graphene was isolated for the first time by Novoselov et al. (<xref ref-type="bibr" rid="B120">2004</xref>) what was worth to them the 2010 Nobel Prize in Physics for their groundbreaking work. Their unprecedented structural and physico-chemical properties (especially its mechanical and electrical behaviors) in addition to its carrier mobility&#x02009;&#x02013;&#x02009;the highest know to date, at room temperature&#x02009;&#x02013;&#x02009;makes the research on graphene one of the most important topics in all materials science fields (Basu and Bhattacharyya, <xref ref-type="bibr" rid="B8">2012</xref>). On the other hand, graphene&#x02019; structure serves as the basic shape of almost all other carbonaceous materials, including fullerene (Muge and Chabal, <xref ref-type="bibr" rid="B112">2011</xref>), single and multi-walled carbon nanotubes (Hassan, <xref ref-type="bibr" rid="B57">2012</xref>), and even graphite, which is simply a multiple layers graphene (Basu and Bhattacharyya, <xref ref-type="bibr" rid="B8">2012</xref>). Literature survey shows that graphene material has numbers of potential applications, including nanoelectronic like-devices, gas sensors, hydrogen storage, and polymer-based nanocomposites (Boukhvalov et al., <xref ref-type="bibr" rid="B15">2008</xref>; Ponnamma et al., <xref ref-type="bibr" rid="B130">2010</xref>; Schwierz, <xref ref-type="bibr" rid="B138">2010</xref>; Casolo et al., <xref ref-type="bibr" rid="B19">2011</xref>), and could serve as an ideal prototype to investigate the properties of many other 2D nanosystems, such as 2D silicon and silicon carbide (2D-<italic>SiC</italic>), zinc oxide, boron nitride, and germanium (Elias et al., <xref ref-type="bibr" rid="B36">2009</xref>; Bekaroglu et al., <xref ref-type="bibr" rid="B10">2010</xref>; Houssa et al., <xref ref-type="bibr" rid="B61">2010</xref>; Tang and Cao, <xref ref-type="bibr" rid="B152">2010</xref>; Voon et al., <xref ref-type="bibr" rid="B157">2010</xref>; Zhang et al., <xref ref-type="bibr" rid="B185">2010a</xref>).</p>
<fig position="float" id="F1">
<label>Figure 1</label>
<caption><p><bold>Various potential applications of graphene material</bold>.</p></caption>
<graphic xlink:href="fmats-02-00058-g001.tif"/>
</fig>
<p>Experimentally measured properties of graphene have not only exceeded those obtained in any other material but also reached very often its theoretically predicted limits. A typical example is its room-temperature carrier mobility, of 2.5&#x02009;&#x000D7;&#x02009;10<sup>5</sup>&#x02009;cm<sup>2</sup>/Vs, which is found to be very close to the theoretical limit of 2&#x02009;&#x000D7;&#x02009;10<sup>5</sup>&#x02009;cm<sup>2</sup>/Vs (Mayorov et al., <xref ref-type="bibr" rid="B105">2011</xref>). Many other representative examples could be found in the relevant literature, just to cite a few: a Young&#x02019;s modulus of 1 TPa very close to that predicted by theory (Liu et al., <xref ref-type="bibr" rid="B95">2007</xref>; Lee et al., <xref ref-type="bibr" rid="B83">2008</xref>; Morozov et al., <xref ref-type="bibr" rid="B110">2008</xref>); a thermal conductivity of 3000&#x02009;W mK<sup>&#x02212;1</sup> (Balandin, <xref ref-type="bibr" rid="B6">2011</xref>); an optical absorption of 2.3% in the infrared (Nair et al., <xref ref-type="bibr" rid="B113">2008</xref>); its property to be completely impermeable to gases (Bunch et al., <xref ref-type="bibr" rid="B17">2008</xref>); its ability to carry one million time higher densities of electrical current than copper (Moser et al., <xref ref-type="bibr" rid="B111">2007</xref>), and its potential to be chemically functionalized (Elias et al., <xref ref-type="bibr" rid="B36">2009</xref>; Loh et al., <xref ref-type="bibr" rid="B96">2010</xref>; Nair et al., <xref ref-type="bibr" rid="B114">2010</xref>). It is worth noting that the majority of these properties have been experimentally measured for a high-quality graphene samples, deposited on specific substrates, such as hexagonal boron nitride (Dean et al., <xref ref-type="bibr" rid="B31">2010</xref>; Mayorov et al., <xref ref-type="bibr" rid="B105">2011</xref>). However, similar properties have not been observed so far on graphene material prepared using classical techniques, although these conventional processes are continuously improving (Neto et al., <xref ref-type="bibr" rid="B117">2009</xref>; Sarma et al., <xref ref-type="bibr" rid="B137">2011</xref>). We conclude then that the challenge related to find markets of graphene applications is mainly related to the real progress realized in its mass production with appropriate characteristics.</p>
<p>The number of publications related to the graphene material is continually growing has increased dramatically especially in last years (from about 4000 in 2010 to more than 14,000 in 2014) (Choi et al., <xref ref-type="bibr" rid="B27">2010</xref>). Figure <xref ref-type="fig" rid="F2">2</xref> shows how the number of refereed articles dealing with graphene material has steadily increased since 2004, based on data collected from the Engineering Village web-based information service.</p>
<fig position="float" id="F2">
<label>Figure 2</label>
<caption><p><bold>(A)</bold> Number of the publications/year on the graphene materials. The inset is the distribution of the document type, where only 2.7% of the publications are related to a review work. <bold>(B)</bold> Distribution of the publications by subject area.</p></caption>
<graphic xlink:href="fmats-02-00058-g002.tif"/>
</fig>
<p>The same tendency is also recorded with patents applications, which have downright doubled within 2&#x02009;years only [i.e., from 2010 to 2012 with a total of 8416 patents worldwide by February 2013 (Zhang et al., <xref ref-type="bibr" rid="B184">2013</xref>)].</p>
<p>In the recent years, there have been many review works, related either to theoretical and/or experimental studies, discussing the topics of synthesis and application of graphene material. To cite just few recent works, Neto et al., (<xref ref-type="bibr" rid="B117">2009</xref>) reviewed the electrical properties of graphene, and then focused on its electronic transport properties (Neto et al., <xref ref-type="bibr" rid="B117">2009</xref>). Other experimental reviews included detailed discussions of synthesis (Zhang et al., <xref ref-type="bibr" rid="B185">2010a</xref>) and Raman spectroscopy processes of transport mechanisms (Ni et al., <xref ref-type="bibr" rid="B118">2008</xref>; Avouris, <xref ref-type="bibr" rid="B3">2010</xref>; Giannazzo et al., <xref ref-type="bibr" rid="B45">2011</xref>), related to electronic applications graphene, including transistors like-devices, bandgap engineering (Loh et al., <xref ref-type="bibr" rid="B96">2010</xref>), and optoelectronic technologies (Bonaccorso et al., <xref ref-type="bibr" rid="B14">2010</xref>; Schwierz, <xref ref-type="bibr" rid="B138">2010</xref>). However, among all the published articles on the matter, only 18 review works have been conducted on the smart applications of the graphene materials (Figure <xref ref-type="fig" rid="F3">3</xref>), and to the best of our knowledge, only one review-article has been published on 2015. In sum, along with the increase in the number of publications in this area comes a need for a comprehensive review article, and the objective of this paper is to address this need. The literature is indeed lacking a comprehensive review of the recent experimental advancements on graphene material and its smart applications. This is the aim of our article. However, due to the huge number of various works that are involved, and often the unavailability of access to many conference proceedings, the emphasis of this paper was on the most accessible refereed journal articles. Obviously, it was not possible and practical to cover all of these articles, especially since a lot of them had already been covered by previous paper review; an attempt was made to select representative articles in each of the relevant categories. This review should be particularly well suited to graduate students who desire an introduction to the study of graphene that will provide them with many references for further reading.</p>
<fig position="float" id="F3">
<label>Figure 3</label>
<caption><p><bold>(A)</bold> Number of the review publications/year on the graphene materials. <bold>(B)</bold> Distribution of the review publications per subject area.</p></caption>
<graphic xlink:href="fmats-02-00058-g003.tif"/>
</fig>
</sec>
<sec id="S2">
<title>Graphene Scalable Synthesis Perspectives</title>
<p>Initially discovered by micromechanical exfoliation of graphite (Geim and Novoselov, <xref ref-type="bibr" rid="B42">2007b</xref>), graphene has generated widespread interest as a smart material. However, for graphene to make a significant impact within industry, it is important to develop methods for scalable synthesis of high-quality graphene. The current common production methods for graphene include liquid exfoliation, ultrahigh vacuum processes, annealing of silicon carbide (<italic>SiC</italic>), and obviously, chemical vapor deposition (CVD). Other methods, which could be used for scalable graphene synthesis, include plasma enhanced CVD, flame synthesis, and pulsed laser deposition (PLD). These methods will be discussed in this review with a focus on identifying processes that can be translated for commercial production of graphene. This review does not cover methods for the production of graphene oxide.</p>
<sec id="S2-1">
<title>Micromechanical exfoliation</title>
<p>Micromechanical exfoliation involves peeling highly ordered pyrolytic graphite (HOPG) using adhesive tape (Novoselov et al., <xref ref-type="bibr" rid="B119">2005</xref>). Since each layer of graphene is bonded to the other layer by van der Waals bonding, it is feasible to cleave HOPG. Normally, the peeling is performed several times. This process can also be used to produce few layers graphene (FLG). While this is the simplest method for the production of graphene and is commonly used in laboratory experiments, the production method is not scalable for large-scale graphene growth.</p>
</sec>
<sec id="S2-2">
<title>Liquid-phase exfoliation</title>
<p>Liquid-phase exfoliation (LPE) involves using a solvent to exfoliate graphite by ultrasonication (Hernandez et al., <xref ref-type="bibr" rid="B59">2008</xref>; Lotya et al., <xref ref-type="bibr" rid="B99">2009</xref>). Commonly used solvents include acetic acid, sulfuric acid, and hydrogen peroxide (Singh et al., <xref ref-type="bibr" rid="B143">2011</xref>). The ultrasonication time is typically 60&#x02009;min with a power of 250&#x02013;500&#x02009;W. Green and Hersam (<xref ref-type="bibr" rid="B48">2009</xref>) reported the use of sodium cholate as a surfactant for the exfoliation of graphene. Moreover, they were able to separate the sheets by density gradient ultracentrifugation, which enabled the isolation of graphene from FLG. LPE can be used for the production of graphene nanoribbons (GNRs) (Li et al., <xref ref-type="bibr" rid="B91">2008</xref>), where the width is &#x0003C;10&#x02009;nm. While LPE represents a scalable method for the production of graphene, large scale film growth remains really challenging.</p>
</sec>
<sec id="S2-3">
<title>Chemical vapor deposition based synthesis</title>
<p>Chemical vapor deposition of graphene involves the use of transition metals, where nickel (Ni) (Reina et al., <xref ref-type="bibr" rid="B133">2008</xref>; Chae et al., <xref ref-type="bibr" rid="B20">2009</xref>; Kim et al., <xref ref-type="bibr" rid="B76">2009</xref>; Losurdo et al., <xref ref-type="bibr" rid="B98">2011</xref>) and copper (Cu) (Li et al., <xref ref-type="bibr" rid="B89">2009</xref>; Bae et al., <xref ref-type="bibr" rid="B4">2010</xref>; Guermoune et al., <xref ref-type="bibr" rid="B49">2011</xref>; Suk et al., <xref ref-type="bibr" rid="B148">2011</xref>; Wang et al., <xref ref-type="bibr" rid="B164">2011</xref>) are suitable for large scale production of graphene.</p>
<p>Graphene growth based on CVD has shown exceptional device properties (Figure <xref ref-type="fig" rid="F4">4</xref>) (Bae et al., <xref ref-type="bibr" rid="B4">2010</xref>), with electron mobility of 7350&#x02009;cm<sup>2</sup>&#x02009;V<sup>&#x02212;1</sup>s<sup>&#x02212;1</sup> (Novoselov et al., <xref ref-type="bibr" rid="B119">2005</xref>). In addition, large scale production of 30&#x02033; graphene films was demonstrated using roll-to-roll CVD (Mattevi et al., <xref ref-type="bibr" rid="B104">2011</xref>). The graphene obtained from this process was of high quality, with a sheet resistance of &#x0007E;125&#x02009;&#x003A9;/square and 97.4% optical transmittance.</p>
<fig position="float" id="F4">
<label>Figure 4</label>
<caption><p><bold>(A)</bold> Schematic of the roll-to-roll production of graphene films grown on a copper foil. <bold>(B)</bold> Roll-to-roll transfer of graphene films from a thermal release tape to a PET film at 120&#x000B0;C. <bold>(C)</bold> A transparent large-area graphene film transferred on a 35&#x02033; PET sheet. <bold>(D)</bold> An assembled graphene/PET touch panel showing mechanical flexibility. Reproduced with permission of Bae et al. (<xref ref-type="bibr" rid="B4">2010</xref>). Copyright 2010, Nature Nanotechnology.</p></caption>
<graphic xlink:href="fmats-02-00058-g004.tif"/>
</fig>
<p>Graphene growth using CVD is fairly straightforward, where a copper or nickel substrate is placed in a reactor at temperatures normally around 1000&#x000B0;C. The initial step in the process is to introduce hydrogen in the reactor. This step is critical to eliminate any oxide layer present in the metal, for the case of Cu this will reduce any native layers of CuO and Cu<sub>2</sub>O. The hydrogen atmosphere also enables the growth of grain boundaries (Mattevi et al., <xref ref-type="bibr" rid="B104">2011</xref>), which is necessary for the growth of high-quality graphene. Afterwards, a hydrocarbon gas (typically methane) is added to the reactor. The hydrocarbon gas provides the necessary carbon species used in the growth of graphene. The hydrocarbon gas to hydrogen ratio plays an important role in the growth of graphene. If insufficient hydrogen is present, this could result in oxidized metal layers being present, which can lead to a disordered graphene structure. By contrast, excess hydrogen has shown to etch away graphene. On polycrystalline substrates, the graphene flakes tend to have different lattice orientations.</p>
<p>Using CVD, graphene is grown onto transition metals, which enables a low-energy pathway by forming intermediate compounds for the growth of graphene. The first row of transition metals Fe, Co, Ni, and Cu is of great interest due to their low cost and high availability. The difference in the carbon solubility between these metals impacts the growth quality, where Fe has the highest and Cu has the lowest carbon solubility. For this reason, Cu is an ideal metal for growing single layer graphene. When using Ni and Co it is common to get up to 10 layers of graphene. Similarly, on Fe it is common to have FLG.</p>
<p>Most practical applications of graphene require that the underlying surface be insulating. For this reason, graphene must be transferred to an insulating surface, such as SiO<sub>2</sub> (Bhaviripudi et al., <xref ref-type="bibr" rid="B11">2010</xref>). Additionally, this transfer is required to measure the optoelectronic properties of the synthesized graphene. The commonly used process to transfer graphene is to first deposit and cure poly (methylmethacrylate) (PMMA) on the metal sheet. Afterwards, etch the Cu metal sheet using iron chloride. This gives a floating sheet of PMMA and graphene, which is rinsed in deionized water. Subsequently, transfer this layer to an insulating surface and use acetone to remove the PMMA layer.</p>
</sec>
<sec id="S2-4">
<title>Plasma enhanced chemical vapor deposition synthesis</title>
<p>Plasma enhanced CVD (PECVD) is another method used for the synthesis of graphene that is comparable to the thermal CVD process (Zhu et al., <xref ref-type="bibr" rid="B188">2007</xref>; Yuan et al., <xref ref-type="bibr" rid="B178">2009</xref>; Kim et al., <xref ref-type="bibr" rid="B74">2011</xref>; Bo et al., <xref ref-type="bibr" rid="B13">2013</xref>). PECVD is based on a number of plasma sources, such as microwave (MW) (Malesevic et al., <xref ref-type="bibr" rid="B102">2008</xref>), radio frequency (RF) (Wang et al., <xref ref-type="bibr" rid="B161">2004</xref>), and direct current (dc) arc discharge (Krivchenko et al., <xref ref-type="bibr" rid="B80">2012</xref>) have been utilized in the growth of graphene. Copper and nickel are typically used as the substrate for PECVD graphene growth; however, a number of additional substrates have also been used (Dato et al., <xref ref-type="bibr" rid="B30">2008</xref>; Bo et al., <xref ref-type="bibr" rid="B13">2013</xref>). A particularly exciting technique is a substrate free method based on the decomposition of ethanol in MW-based PECVD reactor (Guermoune et al., <xref ref-type="bibr" rid="B49">2011</xref>). Such methods provide can be used for scalable production of graphene powder. Typical growth conditions of PECVD graphene on a substrate are 5&#x02013;100% CH<sub>4</sub> in H<sub>2</sub> with a substrate temperature of 500&#x02013;800&#x000B0;C (Singh et al., <xref ref-type="bibr" rid="B143">2011</xref>; Bo et al., <xref ref-type="bibr" rid="B13">2013</xref>). The power of the plasma is 900&#x02009;W. Such processes can enable the growth of graphene at lower temperatures and shorter duration (&#x0003C;5&#x02009;min). However, the quality of the graphene film is typically lower when compared to thermal CVD.</p>
<p>The growth of graphene films at low temperature is important for a number of applications. For instance, fabrication of graphene for high-performance display glass has to be at a temperature lower than 660&#x000B0;C (Ren et al., <xref ref-type="bibr" rid="B135">1998</xref>; Bo et al., <xref ref-type="bibr" rid="B13">2013</xref>). Furthermore, production at lower temperature can provide new manufacturing opportunities in the area of flexible electronics based on plastics (Tung et al., <xref ref-type="bibr" rid="B154">2009</xref>). Critical challenges still need to be overcome, as at lower temperatures the graphene film tends to have a higher disorder.</p>
</sec>
<sec id="S2-5">
<title>Flame synthesis</title>
<p>Flame synthesis is extensively used to produce commercial quantities of nanoparticles. Of the most widely used nanoparticles, carbon black, fumed silica, and titania, flame synthesis is the dominant method in the production of these materials. Volumetric production of the flame synthesis industry is on the order of 100 metric tons per day (Kammler et al., <xref ref-type="bibr" rid="B69">2001</xref>). A key advantage of flames is that it readily provides the high temperature necessary for gas-phase synthesis along with a carbonizing or oxidizing environment.</p>
<p>With respect to graphene, flame synthesis is not as commonly studied when compared to CVD, but it offers several important advantages, such as scalability and cost effectiveness. The most commonly used flame types include premixed, normal diffusion, inverse diffusion, and co-flow (Inoue et al., <xref ref-type="bibr" rid="B65">2010</xref>; Memon et al., <xref ref-type="bibr" rid="B109">2013</xref>). Since early 2000s, a number of researchers have focused on the use of flames for CNT synthesis (Inoue et al., <xref ref-type="bibr" rid="B65">2010</xref>). However, the development of flame synthesis for graphene is still in its early stage. In addition to flame type, other parameters including temperature, species concentration, and velocity impact the growth process. Graphene being a two-dimensional material requires large-scale production across a substrate. Due to the temperature and species gradients that occur in most flames it is difficult to scale the growth of graphene across an entire substrate. Moreover, a reduced environment with carbon rich species, which is necessary for graphene growth, is difficult to achieve in most flames. Nevertheless, flame synthesis has the potential to economically enable the mass production of graphene.</p>
<p>Similar to earlier CNT flame synthesis papers, where the growth of CNTs was observed near the soot region of a premixed flame, carbon particles containing graphene were observed in Bunsen (propane) flame (Ossler et al., <xref ref-type="bibr" rid="B122">2010</xref>). These particles were collected by placing a transmission electron microscopy grid 2&#x02009;cm above the tip of the burner. The grid was held within the flame for 10&#x02013;50&#x02009;ms. The graphene films were several hundreds of nanometers in size.</p>
<p>In an attempt to grow graphene on copper, Li et al. (<xref ref-type="bibr" rid="B94">2011b</xref>) investigated the growth of graphene using an ethanol burner. The substrate was placed within the flame at a temperature of 550&#x02013;700&#x000B0;C and the flame was extinguished using a cap to prevent the oxidation of the copper foil. The growth of an amorphous carbon film was observed on the substrate and XPS confirmed the formation of sp<sup>2</sup>, sp<sup>3</sup>, and C&#x02013;O bonded atoms. Graphene was not observed due to the low temperature and the presence of oxygen within the flame. In a different experiment, Li et al. (<xref ref-type="bibr" rid="B93">2011a</xref>) were able to synthesis graphene successfully on nickel. The process utilized two different burners (burner 1 and burner 2), with the substrate situated within the interior region of the flame structure itself (Figure <xref ref-type="fig" rid="F5">5</xref>). Burner 1 (alcohol burner) surrounded the substrate for the entire time, where it prevented air oxidation and served as the carbon source. Burner 2 (butane-fueled Bunsen burner) provided the additional heating of the substrate and served as the carbon source for graphene growth. The flame was extinguished using a cap. There are still numerous challenges in using flame synthesis for the growth of graphene, specifically in developing methods that result in higher quality graphene.</p>
<fig position="float" id="F5">
<label>Figure 5</label>
<caption><p><bold>Different configurations used for the flame synthesis of graphene, (A) dual flame configuration, (B) multiple inverse diffusion flames, (C) flame spray pyrolysis and (D) microcombustor</bold>. Reproduced with permissions from Luechinger et al. (<xref ref-type="bibr" rid="B100">2008</xref>), Li et al. (<xref ref-type="bibr" rid="B94">2011b</xref>), Memon et al. (<xref ref-type="bibr" rid="B108">2011</xref>), and Kellie et al. (<xref ref-type="bibr" rid="B72">2013</xref>).</p></caption>
<graphic xlink:href="fmats-02-00058-g005.tif"/>
</fig>
</sec>
<sec id="S2-6">
<title>Epitaxial growth on silicon carbide substrate</title>
<p>Yannopoulos et al. (<xref ref-type="bibr" rid="B170">2012</xref>) have investigated the thermal decomposition of <italic>SiC</italic> surface, which was providing an epitaxial growth of graphene material (Figure <xref ref-type="fig" rid="F6">6</xref>). They reported a new process using a CO<sub>2</sub> laser as the heating step for a fast and one-step growth process of large uniform graphene film on <italic>SiC</italic>. This method can control the stacking order of epitaxial graphene and is cost-effective since it does not involve any pretreatment step or high-vacuum process. The decomposition operated at low temperature and proceeded in the second time scale, thus providing a means to engineering graphene patterns on <italic>SiC</italic> by focused laser beams.</p>
<fig position="float" id="F6">
<label>Figure 6</label>
<caption><p><bold>(A)</bold> Schematic diagram of the CO<sub>2</sub> laser induced epitaxial growth of graphene on <italic>SiC</italic> wafers. <bold>(B)</bold> SEM micrograph showing the formation of epitaxial growth graphene (Zone 1) on 6H-<italic>SiC</italic> (0001). Reproduced with the permission from Yannopoulos et al. (<xref ref-type="bibr" rid="B170">2012</xref>). Copyright 2012, Wiley-VCH.</p></caption>
<graphic xlink:href="fmats-02-00058-g006.tif"/>
</fig>
</sec>
<sec id="S2-7">
<title>Pulsed laser deposition</title>
<p>The PLD process is definitely considered as one of the most versatile growth approaches. Since the laser energy source is located outside the deposition chamber; the use of either ultrahigh vacuum or ambient gas becomes possible (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>). Combined with a stoichiometry transfer between ablated target and substrate where the material is deposited, this flexibility allows depositing theoretically all possible kinds of materials, including polymers or fullerenes (Eason et al., <xref ref-type="bibr" rid="B35">2006</xref>). This technique was first employed by Smith et al. (<xref ref-type="bibr" rid="B145">1965</xref>) (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>) in 1965 to elaborate semiconductors and dielectric thin films. In 1987, it was then fully developed by Dijkkamp et al. (<xref ref-type="bibr" rid="B32">1987</xref>) for the deposition of high-temperature superconductors. Their work allowed to define the main characteristics of PLD, namely, the stoichiometry transfer between target and deposited film (Smith et al., <xref ref-type="bibr" rid="B145">1965</xref>; Dijkkamp et al., <xref ref-type="bibr" rid="B32">1987</xref>; Chrisey and Hubler, <xref ref-type="bibr" rid="B28">1994</xref>; Eason et al., <xref ref-type="bibr" rid="B35">2006</xref>). Since the work of Dijkkamp et al., the deposition technique has been extensively used for all kinds of oxides, nitrides, carbides and also for preparing metallic systems and even polymers or fullerenes (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>). During PLD, almost all experimental parameters can be adjusted to control the film growth, and ranging from the laser parameters (Fluence, wavelength, pulse-duration, and repetition rate), to the deposition conditions (target-to-substrate distance, temperature, nature of the gas, pressure, etc.).</p>
<p>A representative schematic diagram for PLD (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>) is shown in Figure <xref ref-type="fig" rid="F7">7</xref>. Inside the vacuum chamber (ultrahigh vacuum, UHV), targets of elementary or alloy elements are struck at an angle of 45&#x000B0; by a high energy focused pulsed laser beam. The atoms and ions ablated from the target(s) are then deposited directly on the substrate (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>). In the majority of the cases, the substrates are attached with their surfaces parallel to the target(s) surfaces at a distance of 2&#x02013;10&#x02009;cm.</p>
<fig position="float" id="F7">
<label>Figure 7</label>
<caption><p><bold>Schematic of a representative laser deposition tool</bold>.</p></caption>
<graphic xlink:href="fmats-02-00058-g007.tif"/>
</fig>
<p>To the benefit of the reader, Figure <xref ref-type="fig" rid="F8">8</xref> summarizes the main first-deposited materials since the introduction of PLD in 1987, with respect to the year for deposition and corresponding reference.</p>
<fig position="float" id="F8">
<label>Figure 8</label>
<caption><p><bold>List of the materials deposited for the first time by PLD after 1987</bold>.</p></caption>
<graphic xlink:href="fmats-02-00058-g008.tif"/>
</fig>
<p>As mentioned earlier, in the PLD process, one of the main advantages is the fact that during deposition, the stoichiometry of the deposited material is very close to the target (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>). Consequently, it is possible to prepare stoichiometric thin films from a single alloy bulk target (Krebs et al., <xref ref-type="bibr" rid="B79">2003</xref>).</p>
<p>In the context of the graphene growth, and in parallel to the CVD deposition method, physical vapor deposition has also been reported for the growth of graphene (Koh et al., <xref ref-type="bibr" rid="B78">2010</xref>; Zhang and Feng, <xref ref-type="bibr" rid="B179">2010b</xref>). In UHV, PLD chambers graphite is normally used as the target with a transition metal as the substrate (Figure <xref ref-type="fig" rid="F9">9</xref>). A substrate temperature of 1300&#x000B0;C was reported for 1&#x02013;2 layers of high-quality graphene (Figure <xref ref-type="fig" rid="F9">9</xref>) (Zhang and Feng, <xref ref-type="bibr" rid="B179">2010b</xref>). No carbide formation occurs at the interface of graphene and the metal (Zhang and Feng, <xref ref-type="bibr" rid="B179">2010b</xref>). While numerous metals can be used as a catalyst, nickel appears to be the most promising for low temperature growth. Numerous parameters, such as the cooling rate and laser power, impact the quality of graphene films (Koh et al., <xref ref-type="bibr" rid="B78">2010</xref>).</p>
<fig position="float" id="F9">
<label>Figure 9</label>
<caption><p><bold>Graphene deposition by means of PLD</bold>. Measured Raman spectra with respect to the growth temperature. Reproduced with permission from Zhang and Feng (<xref ref-type="bibr" rid="B179">2010b</xref>). Copyright 2010, Elsevier.</p></caption>
<graphic xlink:href="fmats-02-00058-g009.tif"/>
</fig>
</sec>
<sec id="S2-8">
<title>Laser-based chemical vapor deposition</title>
<p>A continuous wave (CW) laser is utilized for laser-based CVD in an enclosed chamber (Figure <xref ref-type="fig" rid="F10">10</xref>A) (Park et al., <xref ref-type="bibr" rid="B126">2011</xref>). The precursor gases used include methane and hydrogen, with Ni foil as the substrate. The synthesis mechanism is based on a vapor&#x02013;liquid&#x02013;solid that only takes nanoseconds to picoseconds. The spectra of the Raman spectroscopy showing the different graphene layers are illustrated in Figure <xref ref-type="fig" rid="F10">10</xref>B. A key advantage of this process is that it can be used for graphene lithography, where the laser can be scanned on specific areas of a metal catalyst enabling direct growth.</p>
<fig position="float" id="F10">
<label>Figure 10</label>
<caption><p><bold>(A)</bold> Schematic of the laser induced CVD process, and <bold>(B)</bold> mea-sured Raman as a function of the number of graphene layers. Reprinted with permission from Park et al. (<xref ref-type="bibr" rid="B126">2011</xref>). Copyright 2011, American Institute of Physics.</p></caption>
<graphic xlink:href="fmats-02-00058-g010.tif"/>
</fig>
</sec>
<sec id="S2-9">
<title>Laser growth directly on silicon and quartz substrates</title>
<p>Sun et al. (<xref ref-type="bibr" rid="B151">2010</xref>) produced graphene on Cu and Ni film using PMMA. Due to the existence of the metal films, the graphene films need be transferred to other substrate using polydimethylsiloxane (PDMS) or PMMA (Kim et al., <xref ref-type="bibr" rid="B76">2009</xref>; Reina et al., <xref ref-type="bibr" rid="B134">2009</xref>; Sun et al., <xref ref-type="bibr" rid="B151">2010</xref>). Silicon wafer is the most important single-crystal substrate used for semiconductor devices and integrated circuits (ICs). Suemitsu et al. (<xref ref-type="bibr" rid="B147">2010</xref>) produced epitaxial graphene on Si substrate. In their approach, a <italic>SiC</italic> film of about 100&#x02009;nm-thick was deposited on the Si wafer before growth, so graphene was grown on the <italic>SiC</italic> surface. Direct growth of graphene on bare Si substrate without any other material is very attractive. Graphene films can form a Schottky junction with Si, which can produce a built-in electric field and realize electron-hole separation, and has been used to fabricate solar cells (Li et al., <xref ref-type="bibr" rid="B92">2010a</xref>; Gunst et al., <xref ref-type="bibr" rid="B51">2011</xref>; Karamitaheri et al., <xref ref-type="bibr" rid="B71">2011</xref>).</p>
<p>Wei and Xu (<xref ref-type="bibr" rid="B165">2012</xref>) have demonstrated the growth of FLG directly on a silicon substrate using a laser irradiation. Silicon substrates were coated with PMMA, which was then evaporated using a CW laser beam. The laser beam also melts the silicon surface and carbon atoms from PMMA separates from the silicon upon cooling to form FLG. A substrate of 1&#x02009;cm&#x02009;&#x000D7;&#x02009;2&#x02009;cm p-type (111)-oriented Si wafer was used to grow graphene. The silicon wafer was first cleaned and the native oxide layer was removed in buffer hydrofluoric acid (HF) solution to form H-terminated silicon surface. A PMMA layer was coated on the Si surface by spin coating, then covered by a quartz wafer of the same size, and then fixed on a sample stage using two spring clamps. The purpose of using the quartz wafer is to maintain a high enough concentration of carbon after PMMA is evaporated and dissociated by laser irradiation. The growth was conducted in a vacuum chamber using a CW that was directed on the Si surface to melt the surface of the Si wafer.</p>
<p>For the synthesis of graphene on metal, two main growth mechanisms were proposed. On Ni, graphene was produced via carbon dissolution and precipitation (Yu et al., <xref ref-type="bibr" rid="B176">2008</xref>). On Cu, the growth can be explained by surface-catalyzed process, which involves carbon nucleation on the Cu surface, and the growth of graphene with the addition of carbon to the edges (Wei and Xu <xref ref-type="bibr" rid="B165">2012</xref>). However, both of these growth mechanisms cannot explain the graphene growth on Si. Cu or Ni maintains solid in the graphene growth process. They found that if the laser power was below the melting point of silicon, there was no graphene grown on the silicon surface.</p>
<p>Similar work has been achieved by Wei et al. (<xref ref-type="bibr" rid="B166">2013</xref>), who grow FLG (2&#x02013;3 layers) on quartz substrate by using a continuous-wave laser by suing a photoresist S-1805 coated on the quartz wafer (thickness 30&#x02009;nm).</p>
</sec>
</sec>
<sec id="S3">
<title>Applications of Graphene Materials in Functional Devices</title>
<p>Graphene research has skyrocketed since the Nobel Prize winners Andre Geim and Konstantin Novoselov published a number of papers on the discovery of graphene 11&#x02009;years ago. Since then, there has been a sharp increase in our scientific knowledge of graphene, as shown by the number of publications and patent applications on graphene (Figure <xref ref-type="fig" rid="F2">2</xref>). However, only a handful of graphene-based devices have entered the market, thus we are in an early stage in the commercialization of this material. Further research and development of graphene are critical to help achieve the full potential of this material and the sections below relate to research work of using graphene in smart applications. Figure <xref ref-type="fig" rid="F11">11</xref> shows attempt of classification of some potential smart applications of graphene material as a function to the corresponding technology readiness level.</p>
<fig position="float" id="F11">
<label>Figure 11</label>
<caption><p><bold>Potential smart applications of graphene material as a function to the technology readiness level</bold>.</p></caption>
<graphic xlink:href="fmats-02-00058-g011.tif"/>
</fig>
<sec id="S3-1">
<title>Photovoltaic cell</title>
<p>Photovoltaic (PV) cell is the device which converts light to electricity (Chapin et al., <xref ref-type="bibr" rid="B23">1954</xref>; Wang et al., <xref ref-type="bibr" rid="B163">2008</xref>). So far, graphene-based solar cells have been demonstrated in dye-sensitized PV cells (Choe et al., <xref ref-type="bibr" rid="B26">2010</xref>; Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>), organic bulk-heterojunction PV cells (Li et al., <xref ref-type="bibr" rid="B88">2010b</xref>; Yin et al., <xref ref-type="bibr" rid="B173">2010</xref>), hybrid ZnO/poly(3-hexylthiophene) (P3HT) PV cells (Li et al., <xref ref-type="bibr" rid="B90">2010c</xref>), Si based PV cells (Shim et al., <xref ref-type="bibr" rid="B142">2011</xref>), and InGaN p-i-n PV cells (Gomez De Arco, <xref ref-type="bibr" rid="B46">2010</xref>).</p>
<p>The functionalization of graphene material either during synthesis process (<italic>in situ</italic>) or post-treatment has demonstrated not only the possibility to control the properties of the surfaces and interfaces but also tailoring its work function (Jo et al., <xref ref-type="bibr" rid="B68">2010</xref>; Guo et al., <xref ref-type="bibr" rid="B52">2011</xref>; He et al., <xref ref-type="bibr" rid="B58">2011</xref>; Wan et al., <xref ref-type="bibr" rid="B159">2011</xref>). In an organic PV cell, the difference in work function between the two conductors creates an electrical field in the organic layer (Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>). To date, the power conversion efficiency (PCE) of graphene-electrode organic solar cells (OSCs) has been reported to be in the range of 0.08&#x02013;2.60% (Wan et al., <xref ref-type="bibr" rid="B159">2011</xref>; Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>), which is indeed much lower than those of conventional OSCs made with ITO electrodes (8.37%) (Stankovich et al., <xref ref-type="bibr" rid="B146">2006</xref>; Chen et al., <xref ref-type="bibr" rid="B24">2010a</xref>; He et al., <xref ref-type="bibr" rid="B58">2011</xref>; Wan et al., <xref ref-type="bibr" rid="B159">2011</xref>; Yu et al., <xref ref-type="bibr" rid="B175">2012</xref>; Saravanakumar et al., <xref ref-type="bibr" rid="B136">2013</xref>; Yokomizo et al., <xref ref-type="bibr" rid="B174">2013</xref>; Sharma et al., <xref ref-type="bibr" rid="B140">2014</xref>). However, the PCE of graphene-electrode OSCs needs to be improved to make graphene film a serious candidate for OSCs (Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>).</p>
</sec>
<sec id="S3-2">
<title>Transparent and flexible electronics</title>
<p>Currently, most of the research groups in electronics devices fabrication are investigating different routes to fabricate flexible and transparent electronic devices for various types of applications, including smart windows, IC cards, displays, LEDs, solar cells, etc. (Wager et al., <xref ref-type="bibr" rid="B158">2003</xref>; Yu et al., <xref ref-type="bibr" rid="B177">2011</xref>; Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>). In materials, graphene is one of the viable aspirants, which have all the required properties, at the same time, such as optical transparency, mechanical flexibility, and high conductivity. In recent years, different research groups have reported the integration of graphene-based composite electrodes, including graphene/pentacene and graphene/SWCNT, into transparent and flexible electronic like-devices, such as transistors, memory devices, and ICs (Wager et al., <xref ref-type="bibr" rid="B158">2003</xref>; Ji et al., <xref ref-type="bibr" rid="B66">2011</xref>; Lee et al., <xref ref-type="bibr" rid="B85">2011</xref>; Yu et al., <xref ref-type="bibr" rid="B177">2011</xref>; Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>).</p>
<p>Pentacene-based organic FETs-devices were elaborated onto a flexible substrate by means of patterning and transfer or transfer and patterning processes (P-T) and (T-P) techniques that are defining the graphene electrodes (Figure <xref ref-type="fig" rid="F12">12</xref>A) (Lee et al., <xref ref-type="bibr" rid="B85">2011</xref>; Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>). As a gate electrodes, a plastic substrate based on PEDOT/PSS was used, and poly-4-vinylphenol (PVP) as cross-linker. The typical transfer response of these organic FET is shown in the Figure <xref ref-type="fig" rid="F12">12</xref>A, where a carrier mobility of 0.01 and 0.12&#x02009;cm<sup>2</sup>/Vs were systematically estimated for the (T-P) and (P-T) processes, respectively (Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>). In addition to the field effect carrier mobility, the overall electronic characteristics of the organic transistors dealing with the (P-T) technique of graphene are superior (Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>). Figure <xref ref-type="fig" rid="F12">12</xref>B is showing the variation of the electrical resistance as a function of the number of graphene layers. However, there is large room for improving these electronic properties, especially the carrier mobility and to make it more feasible to use in large scale applications (Jo et al., <xref ref-type="bibr" rid="B67">2012</xref>).</p>
<fig position="float" id="F12">
<label>Figure 12</label>
<caption><p><bold>(A)</bold> Graphical representation and optical photo of an optically transparent and mechanically flexible FETs using graphene as source and drain electrodes. <bold>(B)</bold> Graphical representation composite graphene/SWCNT composite electrode network in FETs and its photograph. Inset in <bold>(A)</bold> shows an image of a mechanically stretched graphene/SWCNT composite based transistor, at the 0 and 50% strain, respectively; the right inset <bold>(B)</bold> is showing the variation of the electrical resistance w/r to the graphene number of layers. Reproduced with permission of Lee et al. (<xref ref-type="bibr" rid="B85">2011</xref>). Copyright 2013, Wiley-VCH.</p></caption>
<graphic xlink:href="fmats-02-00058-g012.tif"/>
</fig>
</sec>
</sec>
<sec id="S4">
<title>Smart Applications of Graphene</title>
<sec id="S4-1">
<title>Thermoelectric application of graphene</title>
<p>Thermoelectric materials (TEM) achieve the conversion between thermal and electrical energy and vice versa. This field has regained renewed attention because of the huge potential of TEM to be applied in Peltier coolers and thermoelectric power generators. It is well established that the performance of TEM are determined mainly by its dimensionless figure of merit, namely ZT. To date, the performance research of TEM have mainly focused on inorganic semiconductors, such as PbTe, Bi<sub>2</sub>Te<sub>3</sub>, CoSb<sub>3</sub>, SnSe, and theirs alloys or composites (Li et al., <xref ref-type="bibr" rid="B86">2010d</xref>). The challenge to develop TEM for a crystalline system with high performance is know how to tailor the interconnected thermoelectric physical parameters, including Seebeck coefficient, the electrical conductivity, and thermal conductivity.</p>
<p>The efficiency of a TEM-based device is usually characterized by the following figure of merit:
<disp-formula id="E1"><mml:math id="M1"><mml:mrow><mml:mi mathvariant="normal">ZT</mml:mi><mml:mo>&#x0003D;</mml:mo><mml:msup><mml:mi mathvariant="normal">S</mml:mi><mml:mn>2</mml:mn></mml:msup><mml:mi mathvariant="normal">&#x003C3;</mml:mi><mml:mi mathvariant="normal">T</mml:mi><mml:mo>/</mml:mo><mml:mi mathvariant="normal">&#x003BA;</mml:mi><mml:mo>,</mml:mo></mml:mrow></mml:math></disp-formula>
where <italic>S</italic> is the Seebeck coefficient (or thermopower, &#x003BC;V/K), &#x003C3; is the electronic conductance (S/m), <italic>T</italic> is the thermal conductivity including contributions from both phonons and electrons (W/mK), and &#x003BA; is the absolute temperature (K).</p>
<p>Figure <xref ref-type="fig" rid="F13">13</xref> shows a schematic illustration of a thermoelectric module for (a) power generation (Seebeck effect) and (b) active generation (Peltier effect). Figure <xref ref-type="fig" rid="F13">13</xref>A shows an applied temperature difference, which causes charge carriers in the material (electron or holes), to diffuse from the hot side to the cold one, resulting in a current flow through the circuit. Figure <xref ref-type="fig" rid="F13">13</xref>B is schematic of the heat that evolves at the upper junction and is adsorbed at the lower junction when a current is made to flow through the circuit.</p>
<fig position="float" id="F13">
<label>Figure 13</label>
<caption><p><bold>Schematic illustration of a thermoelectric module for (A) power generation (seebeck effect) and (B) active generation (Peltier effect)</bold>. Reproduced with the Permission from Li et al. (<xref ref-type="bibr" rid="B86">2010d</xref>). Copyright 2010, NPG Asia Mater.</p></caption>
<graphic xlink:href="fmats-02-00058-g013.tif"/>
</fig>
<p>Recently, great effort has been made in improving the TEM dimensionless figure of merit (ZT). The difficulty in to simultaneously optimizing them, which causes thermoelectric research to stagnate for a while, until great reductions in thermal conductivity were theoretically and experimentally proven in nanostrtuctured materials.</p>
<p>Ghosh et al. (<xref ref-type="bibr" rid="B44">2010</xref>) examined the evolution of the thermal properties of FLG with respect to increasing thickness (i.e., the number of graphene layer, <italic>n</italic>). The results obtained by Raman spectroscopy have shown that, overall, the thermal conductivity decreases with increasing the FLG thickness, approaching that of the bulk graphite limit (Figure <xref ref-type="fig" rid="F14">14</xref>) (Ghosh et al., <xref ref-type="bibr" rid="B44">2010</xref>). The experimental data points in Figure <xref ref-type="fig" rid="F14">14</xref> were all normalized to the same width of graphene sheet of 5&#x02009;&#x003BC;m (Ghosh et al., <xref ref-type="bibr" rid="B44">2010</xref>). The detailed procedure is described in Ghosh et al. (<xref ref-type="bibr" rid="B44">2010</xref>).</p>
<fig position="float" id="F14">
<label>Figure 14</label>
<caption><p><bold>Thermal conductivity with respect to the number for atomic planes of quasi-2D carbon materials</bold>. Experimental and simulated thermal conductivity of suspended FLG as a function of number of atomic layer, <italic>n</italic>, taken at the fixed width, <italic>W</italic> of the graphene flake. Reproduced with the permission from Ghosh et al. (<xref ref-type="bibr" rid="B44">2010</xref>). Copyright 2011, Nature Materials.</p></caption>
<graphic xlink:href="fmats-02-00058-g014.tif"/>
</fig>
<p>The evolution observed from 2D graphene to bulk graphite is explained by the cross-plane coupling of the low-energy phonons and changes in the phonon scattering, since more states are available for scattering owing to the increased number of phonon branches. The thermoelectric power (TEP) is the voltage developed across a sample when a constant temperature gradient is applied. TEP of 80&#x02009;&#x003BC;V<italic>/</italic>K was recently measured in graphene at room temperature (300&#x02009;K) (Zuev et al., <xref ref-type="bibr" rid="B189">2009</xref>). Similar to the quantum Hall effect in electronic transport, quantized TEP has also been observed in graphene at high-magnetic fields (Zuev et al., <xref ref-type="bibr" rid="B189">2009</xref>). The TEP can be tuned in graphene, even to negative values, under the application of a gate bias or chemical potential (Wei et al., <xref ref-type="bibr" rid="B167">2009</xref>). Very large TEP values have been predicted for GNRs, for instance, 4&#x02009;mV<italic>/</italic>K for a 1.6&#x02009;nm wide ribbon (Haskins et al., <xref ref-type="bibr" rid="B56">2009</xref>). In comparison, the highest value experimentally reported so far is 850&#x02009;&#x003BC;V<italic>/</italic>K for two-dimensional electron gases in SrTi<sub>2</sub>O<sub>3</sub> heterostructures (Ohta et al., <xref ref-type="bibr" rid="B121">2007</xref>), while only a few &#x003BC;V<italic>/</italic>K has been reported for bulk graphite (Tyler et al., <xref ref-type="bibr" rid="B155">1953</xref>). The TEP power of single walled carbon nanotubes (SWNTs) has been theoretically and experimentally shown to be 60&#x02009;&#x003BC;V<italic>/</italic>K (Hone et al., <xref ref-type="bibr" rid="B60">1998</xref>), inferior to that of graphene. A giant thermoelectric coefficient of 30&#x02009;mV<italic>/</italic>K was reported in metallic electrodes periodically patterned over graphene, deposited on SiO<sub>2</sub> substrate (Chang et al., <xref ref-type="bibr" rid="B21">2007</xref>).</p>
<p>On the other hand, thermoelectric properties of graphene have attracted increased interest as well, since it can convert heat to electricity and vice versa. A high thermopower value of 80&#x02009;&#x003BC;V<italic>/</italic>K was reported for graphene (Zhu et al., <xref ref-type="bibr" rid="B187">2009</xref>; Zuev et al., <xref ref-type="bibr" rid="B189">2009</xref>). Various structures of graphene have been examined, including nanoribbons (GNRs) (Haskins et al., <xref ref-type="bibr" rid="B56">2009</xref>; Sevin&#x000E7;li et al., <xref ref-type="bibr" rid="B139">2009</xref>; Ouyang and Hu, <xref ref-type="bibr" rid="B124">2010</xref>; Huang et al., <xref ref-type="bibr" rid="B64">2011</xref>; Mazzamuto et al., <xref ref-type="bibr" rid="B106">2011</xref>), quantum dots (Yan et al., <xref ref-type="bibr" rid="B169">2012</xref>), graphene junctions, and chevron-type structures (Chen et al., <xref ref-type="bibr" rid="B25">2010b</xref>). It is worth noted here that ZT of zigzag GNRs can exceed 3 (Ouyang and Hu, <xref ref-type="bibr" rid="B124">2010</xref>).</p>
<p>Recently, many works have been conducted on the creation of graphene band gap by means of making an array of holes (antidots) into the graphene layer (Pedersen et al., <xref ref-type="bibr" rid="B127">2008</xref>; Ouyang et al., <xref ref-type="bibr" rid="B123">2011</xref>; Petersen et al., <xref ref-type="bibr" rid="B129">2011</xref>; Chang and Nikolic, <xref ref-type="bibr" rid="B22">2012</xref>). This is an inevitable property for the integration of graphene material directly into transistor architecture (Ouyang et al., <xref ref-type="bibr" rid="B123">2011</xref>; Petersen et al., <xref ref-type="bibr" rid="B129">2011</xref>). The gap can be engineered by controlling the lattice geometry (i.e., the antidot size and the hole-to-hole separation) (Shen et al., <xref ref-type="bibr" rid="B141">2008</xref>; Eroms and Weiss, <xref ref-type="bibr" rid="B37">2009</xref>; Bai et al., <xref ref-type="bibr" rid="B5">2010</xref>; Kim et al., <xref ref-type="bibr" rid="B77">2010</xref>; Gunst et al., <xref ref-type="bibr" rid="B51">2011</xref>; Karamitaheri et al., <xref ref-type="bibr" rid="B71">2011</xref>). Further, thermoelectric properties of these structures (2D graphene antidot lattices) have also been investigated where ZT up to 0.3 was found (Li et al., <xref ref-type="bibr" rid="B86">2010d</xref>).</p>
</sec>
<sec id="S4-2">
<title>Graphene in shape memory materials</title>
<p>Shape memory polymers (SMPs) are defined as smart materials, with the faculty to respond to an external stimulus, typically heat, and have a wide-range of applications from biomedical devices to space materials (Han and Chun., <xref ref-type="bibr" rid="B54">2014</xref>). Polyurethane (PU) is the most attractive SMP material, commonly referred to as SMP polyurethane (SMPU) (Lee et al., <xref ref-type="bibr" rid="B84">2014</xref>). Based on the specific molecular design, SMPU can form either a crystalline or amorphous structure, with a broad actuation temperature range from &#x02212;20 to 150&#x000B0;C (Kim et al., <xref ref-type="bibr" rid="B75">2014</xref>). SMP composites based on nanofillers have shown to increase the overall shape memory properties. An exciting research area is the use of carbon-based nanomaterials, particularly graphene, as nanofillers for SMPUs.</p>
<p>Han and Chun (<xref ref-type="bibr" rid="B54">2014</xref>) prepared a graphene/PU composite material by functionalizing graphene with diazonium salts carrying phenethyl alcohol. The resulting material showed enhanced shape memory, thermal, and mechanical properties. The resulting material showed shape fixity up to 98 with 94% shape recovery ratio after four cycles. Hysteresis loss can be low as 2%. Rana et al. (<xref ref-type="bibr" rid="B132">2013</xref>) prepared a flexible and conductive shape memory composite based on PU and functionalized graphene sheets. The graphene sheets were functionalized using phenyl isocyanate and poly diol. The composite resulted in 97% shape recovery and 95% shape fixity (see Figure <xref ref-type="fig" rid="F15">15</xref>). Modifications to PU can also improve the shape memory performance with graphene. Thakur et al. (<xref ref-type="bibr" rid="B153">2013</xref>) have demonstrated that castor oil-modified hyperbranched PU and graphene-oxide (without functionalization) can result in a shape recovery of &#x0007E;99.5% with shape fixity of &#x0007E;90%. Park et al. (<xref ref-type="bibr" rid="B125">2014</xref>) have demonstrated that PU and allyl isocyanate modified graphene oxide can also be actuated by infrared absorption, with a resulting shape recovery of 90%.</p>
<fig position="float" id="F15">
<label>Figure 15</label>
<caption><p><bold>Shape recovery behavior of graphene-cross linked PU composites, for a temporary helix shape (left) to a permanent shape when applying a constant voltage of 50&#x02009;V</bold>. Reproduced with permission from Rana et al. (<xref ref-type="bibr" rid="B132">2013</xref>). Copyright 2013, Royal Society of Chemistry.</p></caption>
<graphic xlink:href="fmats-02-00058-g015.tif"/>
</fig>
</sec>
<sec id="S4-3">
<title>Graphene in self-healing materials</title>
<p>Long-term stability and durability of materials are one of the main challenges faced today for structural and coating applications, especially when using polymeric composites materials. Indeed, there are many parameters affecting the degradation of materials, including environmental conditions of large types (temperature gradient, UV irradiation, oxygen erosion, corrosion, etc.). As indicated by their name, self-healing materials are first conceived and then designed and elaborated to have the potential to heal mainly the mechanical properties of the materials when damaged. Representative applications of self-healing materials are found in composite polymers, various metals, ceramics, and their related composites, which are subjected to a wide variety of healing principles.</p>
<p>Recently, a few studies have demonstrated the potential of graphene as an additive for self-healing materials. Dong et al. (<xref ref-type="bibr" rid="B33">2013</xref>) synthesized a composite material of poly(acrylamide) (PAM), poly(acrylic acid) (PAA), and graphene that exhibits shape memory effect and self-healing ability. Graphene content was in the range of 10&#x02013;30% and the material can be recovered after 20 cycles of cut and self-healing. The self-healing capabilities are illustrated in Figure <xref ref-type="fig" rid="F16">16</xref>, where 10&#x02009;wt.% graphene sample is cut in the middle and the two pieces were healed together at 37&#x000B0;C for 20&#x02009;min. The results suggest that the self-healing ability and shape memory effect occur due to a &#x0201C;zipper effect&#x0201D; of PAM&#x02013;PAA that forms or dissociate the hydrogen-bond network, where such effects are limited without the addition of graphene. Huang et al. (<xref ref-type="bibr" rid="B63">2013</xref>) have demonstrated the use of FLG with thermoplastic polyurethane (TPU) as self-healing material initiated using an electric stimulus. When the FLG loading rate is 5&#x02009;wt.%, the material can be healed to an efficiency higher than 98% in 3&#x02009;min. Furthermore, upon increasing the FLG loading rate to 8&#x02009;wt.%, the same healing efficiency of 98% can be achieved in 15&#x02009;s only. It is expected that graphene efficiently converts electrical energy to thermal energy, which improves the self-healing ability of TPU diffusion and re-entanglement of the TPU chains. More recently, Wang et al. (<xref ref-type="bibr" rid="B160">2013</xref>) and Sullivan et al. (<xref ref-type="bibr" rid="B149">1977</xref>) have recently reported the fabrication of a composite based on a cross-linked (CL) hydrogen bonding polymer with graphene oxide. This composite material was found to enable a fast self-healing capability, with high efficiency, occurring at room-temperature. More importantly, the healing reaction was produced without the need of any external stimuli, such as electrical bias, light, and heat (Zhang et al., <xref ref-type="bibr" rid="B180">2014</xref>). The introduction of the graphene material in this CL-based polymer was found to be crucial to reduce the needed amount of CL sites that are necessary for the healing reaction. It is worth noting here that a huge amount of CL sites are not only negatively impacting the mechanical properties of the polymer (including flexibility) but also its dynamic characteristics (Zhang et al., <xref ref-type="bibr" rid="B180">2014</xref>). Such nanocomposite materials involving CL-hydrogen bonding polymer with graphene-oxide can be useful in many applications, e.g., protecting barrier for electronic devices, sealing layer for gas systems, and stretchable self-healing conductive wires (Zhang et al., <xref ref-type="bibr" rid="B180">2014</xref>).</p>
<fig position="float" id="F16">
<label>Figure 16</label>
<caption><p><bold>SEM image of G-PAM-PAA strip heating at 37&#x000B0;C in different times, (A) 0&#x02009;min, (B) 10&#x02009;min, and (C) 20&#x02009;min</bold>. <bold>(A&#x02032;&#x02013;C&#x02032;)</bold> are close-up view of the factures occurred in <bold>(A&#x02013;C)</bold>, respectively. Percentage of the recovery ratio as a function of <bold>(D)</bold> healing-time and <bold>(E)</bold> self-healing number (N). Reproduced with permission from Dong et al. (<xref ref-type="bibr" rid="B33">2013</xref>). Copyright 2013, Wiley-VCH.</p></caption>
<graphic xlink:href="fmats-02-00058-g016.tif"/>
</fig>
</sec>
<sec id="S4-4">
<title>Graphene in photomechanical actuators</title>
<p>Actuators are materials, which change their shape or dimensions under the application of external stimulus. To date, the well-recognized materials for actuation are piezoelectrics (Nakamura et al., <xref ref-type="bibr" rid="B115">1989</xref>), ferro-electrics (Kuribayashi et al., <xref ref-type="bibr" rid="B81">1989</xref>), shape memory alloys (Damjanovic and Newnham, <xref ref-type="bibr" rid="B190">1992</xref>), electrostrictive materials (Damjanovic and Newnham, <xref ref-type="bibr" rid="B190">1992</xref>), and conducting polymers (Smela et al., <xref ref-type="bibr" rid="B144">1999</xref>). Recently, large stresses and strains from low-voltage electromehcanical actuation have exhibited by carbon nanotubes (CNTs) (Baughman et al., <xref ref-type="bibr" rid="B9">1999</xref>) and porous metallic nanoparticles (Ahir and Terentjev, <xref ref-type="bibr" rid="B1">2005</xref>). Beside this, both single walled CNT (SWCNT) and multiwalled CNT (MWCNT)-based composites have been reported to undergo photomechanical actuation (Dreyer et al., <xref ref-type="bibr" rid="B34">2010</xref>).</p>
<p>Several articles have reported about graphene-based composites, mostly in sheets form and have derived from graphite oxide or graphite intercalation compounds (GICs). It has been observed that intrusion of graphite oxide or graphite intercalation compounds derived fillers can enhance electrical conductivities of polymeric matrices (G&#x000F3;mez-Navarro et al., <xref ref-type="bibr" rid="B47">2008</xref>), the Young&#x02019;s moduli (Potts et al., <xref ref-type="bibr" rid="B131">2011</xref>), and could easily be functionalized to tailor to host polymer properties (Sun et al., <xref ref-type="bibr" rid="B150">2009</xref>). Now, it is well-known that by tailoring the number of layers of graphene nanoplateletes (GNP) and GNR, the overall properties of composite material change [such as saturable absorption (Casiraghi et al., <xref ref-type="bibr" rid="B18">2007</xref>) and electric field assisted band gaps (Zhang et al., <xref ref-type="bibr" rid="B183">2009</xref>)].</p>
<p>Loomis et al. (<xref ref-type="bibr" rid="B97">2012</xref>) have reported that a simple polymer composite system with photomechanical responses is realized solely by incorporation of a homogeneous dispersion of GNPs within a PDMS elastomer matrix. It has been observed that the actuation responses of GNPs/PDMS composites depend on the initial applied pre-strain as in CNT/PDMS composites. Photomechanical stress change 2.4&#x02013;3.6 times is greater for GNP/PDMS composites, compared to any other tested form of nanocarbon. These stress changes reported are usable and recoverable work achieved by the actuators. Energy conversion factor (&#x003B7;M) of 7&#x02013;9&#x02009;MPa W<sup>&#x02212;1</sup> for optical-to-mechanical is obtained during testing. Until now, this is a largest energy conversion factor of an extraordinary photomechanical effect exhibited by any material so far.</p>
</sec>
<sec id="S4-5">
<title>Graphene in piezoelectric materials</title>
<p>Piezoelectric material has the property of converting mechanical movement into electrical movement and vice versa. Traditionally, piezoelectricity is considered to be an intrinsic property of a particular material phase. Piezoelectric materials have been frequently used in a wide variety of applications from pressure sensors (Pereira and Castro Neto, <xref ref-type="bibr" rid="B128">2009</xref>), to acoustic transducers (Guinea et al., <xref ref-type="bibr" rid="B50">2010</xref>), to high voltage generators (Bunch et al., <xref ref-type="bibr" rid="B16">2007</xref>) for dynamical control of material deformation by application of external electric force.</p>
<p>Luk&#x02019;yanchuk et al. (<xref ref-type="bibr" rid="B101">2015</xref>) have found that piezoelectricity can be concocted into intrinsically non-piezoelectric materials such as graphene. This is a nanoscale new phenomenon and lacking a direct bulk analog (Luk&#x02019;yanchuk et al., <xref ref-type="bibr" rid="B101">2015</xref>). This new phenomenon has provided room for practical approach toward manipulation and dynamic control different concerns in nanodevices, such as optical, chemical, and electronic. Luk&#x02019;yanchuk et al. (<xref ref-type="bibr" rid="B101">2015</xref>) have reported an extraordinary two dimensional piezoelectric effect, both on a strained and unstrained graphene junction. Interestingly, it has been formally attested that this 2D piezo effect is a direct consequence of the difference in the two work functions (of the two type of graphene) and hence to the charge transfer occurring from the biaxial strain when putting the two graphene types together (i.e., bend band structure). The effect has termed as the band-piezoelectric effect, which exhibits a massive magnitude due to the ultrathin structure of graphene (Luk&#x02019;yanchuk et al., <xref ref-type="bibr" rid="B101">2015</xref>).</p>
<p>Using this new type of piezo effect, a piezoelectric nanogenerator and a piezoresistive pressure sensor within a graphene nano-electro-mechanical-system (NEMS) platform have been demonstrated. In this novel device, the deformation caused by an AFM tip resulted in charge separation, due to the modified band structure of the bent membrane (Luk&#x02019;yanchuk et al., <xref ref-type="bibr" rid="B101">2015</xref>). Consequently, by using appropriate metal electrodes with suited work function, we can even collect the cumulated charge and produce an electrical voltage (Luk&#x02019;yanchuk et al., <xref ref-type="bibr" rid="B101">2015</xref>).</p>
</sec>
<sec id="S4-6">
<title>Graphene in electrorheology materials</title>
<p>Electrorheology (ER) material is a type of smart material where the rheological properties of the material can be reversibly transformed with the application of an external electric field (Zhang et al., <xref ref-type="bibr" rid="B186">2010c</xref>, <xref ref-type="bibr" rid="B182">2012</xref>; Yin et al., <xref ref-type="bibr" rid="B171">2012</xref>; Zhang and Choi, <xref ref-type="bibr" rid="B181">2014</xref>). An ER material is composed of polarizable particles suspended in an insulating medium and after applying an electric field the particles are polarized and form a column like structure. This modifies the rheological properties of the material, such as viscosity, shear stress, and dynamic modulus. Applications of such materials include damper systems, ER polishing, tactile displays, medical devices, and robotic actuators. Recently, graphene, r-GO, and GO, due to their unique properties, have gathered the interest of the scientific community as an additive for ER materials (Zhang and Choi, <xref ref-type="bibr" rid="B181">2014</xref>). Zhang et al. (<xref ref-type="bibr" rid="B186">2010c</xref>) prepared colloidal r-GO using a modified Hummers method, which was used to prepare a nanocomposite material comprising of GO and polyaniline (PANI). The resulting material showed adjustable electrical conductivity, which has potential for use as an ER material. Additionally, Zhang et al. (<xref ref-type="bibr" rid="B182">2012</xref>) also prepared GO particles suspended in silicone oil, where the ER fluid is polarized and exhibits viscoelastic properties at various strains under an electric field.</p>
<p>Yin et al. (<xref ref-type="bibr" rid="B171">2012</xref>) prepared a novel ER suspension comprising of two dimensional PANI decorated GO sheets. With the application of an electric field, the suspension containing PANI and GO, shows higher ER effect when compared to pure PANI. The performance of the material is dependent on the thickness of the PANI coating applied to the GO sheets. Furthermore, Yin et al. (<xref ref-type="bibr" rid="B172">2013</xref>) prepared mesoporous silica-coated r-GO nanosheets as a dispersal for ER fluids. Silica coating limits the conductivity of graphene, which enables high polarization and ER response, with the application of an electric field particularly high-frequency AC electric fields. The silica shells also limit the restacking of graphene. Li et al. (<xref ref-type="bibr" rid="B87">2015</xref>) studied the ER effects of non-conducting GO and conducting r-GO comprise an insulating SiO<sub>2</sub> shell. The results show that the GO/SiO<sub>2</sub> has a higher ER response to DC and low-frequency AC electric fields, while the r-GO/SiO<sub>2</sub> has a higher ER response to high-frequency AC electric fields. The different behavior can be explained by the impact of the polarization rate with regards to the inter-particle interaction.</p>
</sec>
<sec id="S4-7">
<title>Multifunctional graphene nanocomposite foams for space applications</title>
<p>Space is the new frontier and new materials, devices, and technologies for aerospace applications represent now an emerging sector with significant employment prospects and opportunities for profit. Materials and devices used in space applications (e.g., satellites) should combine functionality with low weight and reduced volume, to optimize cost effectiveness. The main cost of a satellite is its launch into orbit (estimated at about 7 M&#x00024;), therefore reducing weight and volume can significantly decrease the overall cost. Weight savings can be achieved by replacing heavy copper wiring, which accounts for example up to 4000&#x02009;lbs of weight on a Boeing 747 and about one-third of the weight of large satellites (Meador et al., <xref ref-type="bibr" rid="B107">2010</xref>), with low density carbon-based wiring cables. In addition, Joule heating from metallic parts requires additional components for cooling (radiators), thus adding to the overall weight and cost. The combination of superior electronic and thermal properties of graphene materials could potentially revolutionize the design and fabrication of light weight electrical and electronic devices to be used in space applications. In this context, graphene is a promising candidate because its ballistic electron transport limits Joule heating and should allow reductions in weight, volume, and subsequently total cost.</p>
<p>Another potential space application of graphene is its use as nanofiller to fabricate light weight and robust nanocomposite, to be used, e.g., as thermal barrier. Recently, graphene nanoplatelets having FLG with 1&#x02013;5 layers and typical diameters ranging from 1 to over 100&#x02009;&#x003BC;m have been successfully grown by a team from Michigan State University<xref ref-type="fn" rid="fn1"><sup>1</sup></xref>. These nanoplatelets show, overall, similar properties to a single graphene layer while being mechanically much robust. In addition, their cost production can be lowered to be competitive to other carbonaceous additives and fillers. These nanoplatelets could be used as a nanoadditive into various polymer foams, increasing thereby their thermal, mechanical, and electrical properties, while the foam still maintains its unique structure and low density. This combination of unique properties has direct potential application as flame resistant in space technology.</p>
</sec>
</sec>
<sec id="S5">
<title>Conclusion and Outlooks</title>
<p>Research on graphene has considerably enriched our understandings and applications of two-dimensional atomic crystal. The combination of unprecedented physical and chemical properties, including its extremely high strength, thermal and electrical conductivity, and mechanical flexibility, have harried scientists to investigate in-depth its real potential in delivering improvements to different devices in many technological and scientific fields, ranging from materials science to physics, chemical engineering, and even biology. In this review, we have presented an overview of the main gas-phase synthesis of graphene and its applications as smart material systems. The possibility of successfully integrating graphene directly into device, could not only improve the electrical and/or mechanical properties but also enable the realization of a wide range of applications, such as actuation, thermoelectricity, shape memory, and self-healing. However, this success is conditioned by the prior success to address the following issues: (i) developing a cost-effective growth process to synthesize functional graphene in a reasonable scale with acceptable degree of reproducibility, for the realization of practical applications; (ii) considering the unique electrical, mechanical, and optical properties of graphene, incorporation of these characteristics into the existing smart systems from an interdisciplinary point of view should be highly valued; (iii) finally, from practical view-point, its highly desirable to fabricate graphene multifunctional systems, that are responsive to multiple stimuli. Considering the current and ongoing achievements, it is believed that the smart applications of graphene systems with more functionality are expected to emerge as new complements&#x02009;&#x02013;&#x02009;and/or even replacements&#x02009;&#x02013;&#x02009;to existing conventional systems, especially in fields of electronics, energy, and space.</p>
</sec>
<sec id="S6">
<title>Conflict of Interest Statement</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
</body>
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<ack>
<p>Authors thank the financial support of the Qatar Environment and Energy Research Institute and Qatar Foundation.</p>
</ack>
<ref-list>
<title>References</title>
<ref id="B1"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ahir</surname> <given-names>S. V.</given-names></name> <name><surname>Terentjev</surname> <given-names>E. M.</given-names></name></person-group> (<year>2005</year>). <article-title>Photomechanical actuation in polymer-nanotube composites</article-title>. <source>Nat. Mater.</source> <volume>4</volume>, <fpage>491</fpage>&#x02013;<lpage>495</lpage>.<pub-id pub-id-type="doi">10.1038/nmat1391</pub-id><pub-id pub-id-type="pmid">15880115</pub-id></citation></ref>
<ref id="B2"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>A&#x000EF;ssa</surname> <given-names>B.</given-names></name> <name><surname>Nechache</surname> <given-names>R.</given-names></name> <name><surname>Haddad</surname> <given-names>E.</given-names></name> <name><surname>Jamroz</surname> <given-names>W.</given-names></name> <name><surname>Merle</surname> <given-names>P. G.</given-names></name> <name><surname>Rosei</surname> <given-names>F.</given-names></name></person-group> (<year>2012</year>). <article-title>Ruthenium Grubbs&#x02019; catalyst nanostructures grown by UV-excimer-laser ablation for self-healing applications</article-title>. <source>Appl. Surf. Sci.</source> <volume>258</volume>, <fpage>9800</fpage>&#x02013;<lpage>9804</lpage>.<pub-id pub-id-type="doi">10.1510/icvts.2010.255588</pub-id></citation></ref>
<ref id="B3"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Avouris</surname> <given-names>P.</given-names></name></person-group> (<year>2010</year>). <article-title>Graphene: electronic and photonic properties and devices</article-title>. <source>Nano Lett.</source> <volume>10</volume>, <fpage>4285</fpage>&#x02013;<lpage>4294</lpage>.<pub-id pub-id-type="doi">10.1021/nl102824h</pub-id><pub-id pub-id-type="pmid">20879723</pub-id></citation></ref>
<ref id="B4"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bae</surname> <given-names>S.</given-names></name> <name><surname>Kim</surname> <given-names>H.</given-names></name> <name><surname>Lee</surname> <given-names>Y.</given-names></name> <name><surname>Xu</surname> <given-names>X.</given-names></name> <name><surname>Park</surname> <given-names>J. S.</given-names></name> <name><surname>Zheng</surname> <given-names>Y.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Roll-to-roll production of 30-inch graphene films for transparent electrodes</article-title>. <source>Nat. Nanotechnol.</source> <volume>5</volume>, <fpage>574</fpage>&#x02013;<lpage>578</lpage>.<pub-id pub-id-type="doi">10.1038/nnano.2010.132</pub-id><pub-id pub-id-type="pmid">20562870</pub-id></citation></ref>
<ref id="B5"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bai</surname> <given-names>J.</given-names></name> <name><surname>Zhong</surname> <given-names>X.</given-names></name> <name><surname>Jiang</surname> <given-names>S.</given-names></name> <name><surname>Huang</surname> <given-names>Y.</given-names></name> <name><surname>Duan</surname> <given-names>X.</given-names></name></person-group> (<year>2010</year>). <article-title>Graphene nanomesh</article-title>. <source>Nat. Nanotechnol.</source> <volume>5</volume>, <fpage>190</fpage>&#x02013;<lpage>194</lpage>.<pub-id pub-id-type="doi">10.1038/nnano.2010.8</pub-id><pub-id pub-id-type="pmid">20154685</pub-id></citation></ref>
<ref id="B6"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Balandin</surname> <given-names>A. A.</given-names></name></person-group> (<year>2011</year>). <article-title>Thermal properties of graphene and nanostructured carbon materials</article-title>. <source>Nat. Mater.</source> <volume>10</volume>, <fpage>569</fpage>&#x02013;<lpage>581</lpage>.<pub-id pub-id-type="doi">10.1038/nmat3064</pub-id><pub-id pub-id-type="pmid">21778997</pub-id></citation></ref>
<ref id="B7"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Balooch</surname> <given-names>M. T.</given-names></name> <name><surname>Tench</surname> <given-names>R. J.</given-names></name> <name><surname>Siekhaus</surname> <given-names>W. J.</given-names></name> <name><surname>Allen</surname> <given-names>M. J.</given-names></name> <name><surname>Connor</surname> <given-names>A. L.</given-names></name> <name><surname>Olander</surname> <given-names>D. R.</given-names></name></person-group> (<year>1990</year>). <article-title>Deposition of SiC films by pulsed excimer laser ablation</article-title>. <source>Appl. Phys. Lett.</source> <volume>57</volume>, <fpage>1540</fpage>&#x02013;<lpage>1542</lpage>.<pub-id pub-id-type="doi">10.1063/1.103346</pub-id></citation></ref>
<ref id="B8"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Basu</surname> <given-names>S.</given-names></name> <name><surname>Bhattacharyya</surname> <given-names>P.</given-names></name></person-group> (<year>2012</year>). <article-title>Recent developments on graphene and graphene oxide based solid state gas sensors</article-title>. <source>Sens. Actuators B Chem.</source> <volume>173</volume>, <fpage>1</fpage>&#x02013;<lpage>21</lpage>.<pub-id pub-id-type="doi">10.1016/j.snb.2012.07.092</pub-id></citation></ref>
<ref id="B9"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Baughman</surname> <given-names>R. H.</given-names></name> <name><surname>Cui</surname> <given-names>C.</given-names></name> <name><surname>Zakhidov</surname> <given-names>A. A.</given-names></name> <name><surname>Iqbal</surname> <given-names>Z.</given-names></name> <name><surname>Barisci</surname> <given-names>J. N.</given-names></name> <name><surname>Spinks</surname> <given-names>G. M.</given-names></name> <etal/></person-group> (<year>1999</year>). <article-title>Carbon nanotube actuators</article-title>. <source>Science</source> <volume>284</volume>, <fpage>1340</fpage>.<pub-id pub-id-type="doi">10.1126/science.284.5418.1340</pub-id><pub-id pub-id-type="pmid">10334985</pub-id></citation></ref>
<ref id="B10"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bekaroglu</surname> <given-names>E.</given-names></name> <name><surname>Topsakal</surname> <given-names>M.</given-names></name> <name><surname>Cahangirov</surname> <given-names>S.</given-names></name> <name><surname>Ciraci</surname> <given-names>S.</given-names></name></person-group> (<year>2010</year>). <article-title>First-principles study of defects and adatoms in silicon carbide honeycomb structures</article-title>. <source>Phys. Rev. B</source> <volume>81</volume>, <fpage>075433</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.81.075433</pub-id></citation></ref>
<ref id="B11"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bhaviripudi</surname> <given-names>S.</given-names></name> <name><surname>Jia</surname> <given-names>X.</given-names></name> <name><surname>Dresselhaus</surname> <given-names>M. S.</given-names></name> <name><surname>Kong</surname> <given-names>J.</given-names></name></person-group> (<year>2010</year>). <article-title>Role of kinetic factors in chemical vapor deposition synthesis of uniform large area graphene using copper catalyst</article-title>. <source>Nano Lett.</source> <volume>10</volume>, <fpage>4128</fpage>&#x02013;<lpage>4133</lpage>.<pub-id pub-id-type="doi">10.1021/nl102355e</pub-id><pub-id pub-id-type="pmid">20812667</pub-id></citation></ref>
<ref id="B12"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Biunno</surname> <given-names>N.</given-names></name> <name><surname>Narayan</surname> <given-names>J.</given-names></name> <name><surname>Hofmeister</surname> <given-names>S. K.</given-names></name> <name><surname>Srivatsa</surname> <given-names>A. R.</given-names></name> <name><surname>Singh</surname> <given-names>R. K.</given-names></name></person-group> (<year>1989</year>). <article-title>Low-temperature processing of titanium nitride films by laser physical vapor deposition</article-title>. <source>Appl. Phys. Lett.</source> <volume>54</volume>, <fpage>1519</fpage>.<pub-id pub-id-type="doi">10.1063/1.101338</pub-id></citation></ref>
<ref id="B13"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bo</surname> <given-names>Z.</given-names></name> <name><surname>Yang</surname> <given-names>Y.</given-names></name> <name><surname>Chen</surname> <given-names>J.</given-names></name> <name><surname>Yu</surname> <given-names>K.</given-names></name> <name><surname>Yan</surname> <given-names>J.</given-names></name> <name><surname>Cen</surname> <given-names>K.</given-names></name></person-group> (<year>2013</year>). <article-title>Plasma-enhanced chemical vapor deposition synthesis of vertically oriented graphene nanosheets</article-title>. <source>Nanoscale</source> <volume>5</volume>, <fpage>5180</fpage>&#x02013;<lpage>5204</lpage>.<pub-id pub-id-type="doi">10.1039/c3nr33449j</pub-id><pub-id pub-id-type="pmid">23670071</pub-id></citation></ref>
<ref id="B14"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bonaccorso</surname> <given-names>F.</given-names></name> <name><surname>Sun</surname> <given-names>Z.</given-names></name> <name><surname>Hasan</surname> <given-names>T.</given-names></name> <name><surname>Ferrari</surname> <given-names>A. C.</given-names></name></person-group> (<year>2010</year>). <article-title>Graphene photonics and optoelectronics</article-title>. <source>Nat. Photon</source> <volume>4</volume>, <fpage>611</fpage>&#x02013;<lpage>622</lpage>.<pub-id pub-id-type="doi">10.1038/nphoton.2010.186</pub-id></citation></ref>
<ref id="B15"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Boukhvalov</surname> <given-names>D. W.</given-names></name> <name><surname>Katsnelson</surname> <given-names>M. I.</given-names></name> <name><surname>Lichtenstein</surname> <given-names>A. I.</given-names></name></person-group> (<year>2008</year>). <article-title>Hydrogen on graphene: electronic structure, total energy, structural distortions and magnetism from first-principles calculations</article-title>. <source>Phys. Rev. B</source> <volume>77</volume>, <fpage>035427</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.77.035427</pub-id></citation></ref>
<ref id="B16"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bunch</surname> <given-names>J. S.</given-names></name> <name><surname>van der Zande</surname> <given-names>A. M.</given-names></name> <name><surname>Verbridge</surname> <given-names>S. S.</given-names></name> <name><surname>Frank</surname> <given-names>I. W.</given-names></name> <name><surname>Tanenbaum</surname> <given-names>D. M.</given-names></name> <name><surname>Parpia</surname> <given-names>J. M.</given-names></name> <etal/></person-group> (<year>2007</year>). <article-title>Electromechanical resonators from graphene sheets</article-title>. <source>Science</source> <volume>315</volume>, <fpage>490</fpage>&#x02013;<lpage>493</lpage>.<pub-id pub-id-type="doi">10.1126/science.1136836</pub-id><pub-id pub-id-type="pmid">17255506</pub-id></citation></ref>
<ref id="B17"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bunch</surname> <given-names>J. S.</given-names></name> <name><surname>Verbridge</surname> <given-names>S. S.</given-names></name> <name><surname>Alden</surname> <given-names>J. S.</given-names></name> <name><surname>van der Zande</surname> <given-names>A. M.</given-names></name> <name><surname>Parpia</surname> <given-names>J. M.</given-names></name> <name><surname>Craighead</surname> <given-names>H. G.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Impermeable atomic membranes from graphene sheets</article-title>. <source>Nano Lett.</source> <volume>8</volume>, <fpage>2458</fpage>&#x02013;<lpage>2462</lpage>.<pub-id pub-id-type="doi">10.1021/nl801457b</pub-id><pub-id pub-id-type="pmid">18630972</pub-id></citation></ref>
<ref id="B18"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Casiraghi</surname> <given-names>C.</given-names></name> <name><surname>Hartschuh</surname> <given-names>A.</given-names></name> <name><surname>Lidorikis</surname> <given-names>E.</given-names></name> <name><surname>Qian</surname> <given-names>H.</given-names></name> <name><surname>Harutyunyan</surname> <given-names>H.</given-names></name> <name><surname>Gokus</surname> <given-names>T.</given-names></name> <etal/></person-group> (<year>2007</year>). <article-title>Rayleigh imaging of graphene and graphene layers</article-title>. <source>Nano Lett.</source> <volume>7</volume>, <fpage>2711</fpage>&#x02013;<lpage>2717</lpage>.<pub-id pub-id-type="doi">10.1021/nl071168m</pub-id><pub-id pub-id-type="pmid">17713959</pub-id></citation></ref>
<ref id="B19"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Casolo</surname> <given-names>S.</given-names></name> <name><surname>Martinazzo</surname> <given-names>R.</given-names></name> <name><surname>Tantardini</surname> <given-names>G. F.</given-names></name></person-group> (<year>2011</year>). <article-title>Band engineering in graphene with superlattices of substitutional defects</article-title>. <source>J. Phys. Chem. C</source> <volume>115</volume>, <fpage>3250</fpage>&#x02013;<lpage>3256</lpage>.<pub-id pub-id-type="doi">10.1021/jp109741s</pub-id></citation></ref>
<ref id="B20"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chae</surname> <given-names>S. J.</given-names></name> <name><surname>G&#x000FC;ne&#x0015E;</surname> <given-names>F.</given-names></name> <name><surname>Kim</surname> <given-names>K. K.</given-names></name> <name><surname>Kim</surname> <given-names>E. S.</given-names></name> <name><surname>Han</surname> <given-names>G. H.</given-names></name> <name><surname>Kim</surname> <given-names>S. M.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Synthesis of large-area graphene layers on poly-nickel substrate by chemical vapor deposition: wrinkle formation</article-title>. <source>Adv. Mater. Weinheim</source> <volume>21</volume>, <fpage>2328</fpage>&#x02013;<lpage>2333</lpage>.<pub-id pub-id-type="doi">10.1002/adma.200803016</pub-id></citation></ref>
<ref id="B21"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chang</surname> <given-names>P.H.</given-names></name> <name><surname>Nikolic</surname> <given-names>B.K.</given-names></name></person-group> (<year>2007</year>). <article-title>Giant thermoelectric effect in graphene</article-title>. <source>Appl. Phys. Lett.</source> <volume>91</volume>, <fpage>203116</fpage>.<pub-id pub-id-type="doi">10.1021/nl500755m</pub-id><pub-id pub-id-type="pmid">24932511</pub-id></citation></ref>
<ref id="B22"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chang</surname> <given-names>P. H.</given-names></name> <name><surname>Nikolic</surname> <given-names>B. K.</given-names></name></person-group> (<year>2012</year>). <article-title>Edge currents and nanopore arrays in zigzag and chiral graphene nanoribbons as a route toward high-ZT thermoelectrics</article-title>. <source>Phys. Rev. B</source> <volume>86</volume>, <fpage>041406</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.86.041406</pub-id></citation></ref>
<ref id="B23"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chapin</surname> <given-names>D. M.</given-names></name> <name><surname>Fuller</surname> <given-names>C. S.</given-names></name> <name><surname>Pearson</surname> <given-names>G. L.</given-names></name></person-group> (<year>1954</year>). <article-title>A new silicon p-n junction photocell for converting solar radiation into electrical power</article-title>. <source>J. Appl. Phys.</source> <volume>25</volume>, <fpage>676</fpage>&#x02013;<lpage>677</lpage>.<pub-id pub-id-type="doi">10.1063/1.1721711</pub-id></citation></ref>
<ref id="B24"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chen</surname> <given-names>Z.</given-names></name> <name><surname>Berciaud</surname> <given-names>S.</given-names></name> <name><surname>Nuckolls</surname> <given-names>C.</given-names></name> <name><surname>Heinz</surname> <given-names>T. F.</given-names></name> <name><surname>Brus</surname> <given-names>L. E.</given-names></name></person-group> (<year>2010a</year>). <article-title>Energy transfer from individual semiconductor nanocrystals to graphene</article-title>. <source>ACS Nano</source> <volume>4</volume>, <fpage>2964</fpage>&#x02013;<lpage>2968</lpage>.<pub-id pub-id-type="doi">10.1021/nn1005107</pub-id><pub-id pub-id-type="pmid">20402475</pub-id></citation></ref>
<ref id="B25"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chen</surname> <given-names>Y.</given-names></name> <name><surname>Jayasekera</surname> <given-names>T.</given-names></name> <name><surname>Calzolari</surname> <given-names>A.</given-names></name> <name><surname>Kim</surname> <given-names>K. W.</given-names></name> <name><surname>Nardelli</surname> <given-names>M. B.</given-names></name></person-group> (<year>2010b</year>). <article-title>Thermoelectric properties of graphene nanoribbons, junctions and superlattices</article-title>. <source>J. Phys. Condens. Matter.</source> <volume>22</volume>, <fpage>372202</fpage>.<pub-id pub-id-type="doi">10.1088/0953-8984/22/37/372202</pub-id><pub-id pub-id-type="pmid">21403189</pub-id></citation></ref>
<ref id="B26"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Choe</surname> <given-names>M.</given-names></name> <name><surname>Lee</surname> <given-names>B. H.</given-names></name> <name><surname>Jo</surname> <given-names>G.</given-names></name> <name><surname>Park</surname> <given-names>J.</given-names></name> <name><surname>Park</surname> <given-names>W.</given-names></name> <name><surname>Lee</surname> <given-names>S.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Efficient bulk-heterojunction photovoltaic cells with transparent multi-layer graphene electrodes</article-title>. <source>Org. Electron.</source> <volume>11</volume>, <fpage>1864</fpage>&#x02013;<lpage>1869</lpage>.<pub-id pub-id-type="doi">10.1016/j.orgel.2010.08.018</pub-id></citation></ref>
<ref id="B27"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Choi</surname> <given-names>W.</given-names></name> <name><surname>Lahiria</surname> <given-names>I.</given-names></name> <name><surname>Seelaboyinaa</surname> <given-names>R.</given-names></name></person-group> (<year>2010</year>). <article-title>Synthesis of graphene and its applications: a review</article-title>. <source>Crit. Rev. Solid State Mater. Sci.</source> <volume>35</volume>, <fpage>52</fpage>&#x02013;<lpage>71</lpage>.<pub-id pub-id-type="doi">10.1080/10408430903505036</pub-id></citation></ref>
<ref id="B28"><citation citation-type="book"><person-group person-group-type="author"><name><surname>Chrisey</surname> <given-names>D. B.</given-names></name> <name><surname>Hubler</surname> <given-names>G. K.</given-names></name></person-group> (<year>1994</year>). <source>Pulsed Laser Deposition of Thin Films</source>. <publisher-loc>New York, NY</publisher-loc>: <publisher-name>John Wiley</publisher-name>.</citation></ref>
<ref id="B29"><citation citation-type="book"><person-group person-group-type="author"><name><surname>Curl</surname> <given-names>R. F.</given-names></name> <name><surname>Smalley</surname> <given-names>R. E.</given-names></name></person-group> (<year>1991</year>). <source>Scientific American</source>, Vol. <volume>33</volume>. <fpage>32</fpage>.</citation></ref>
<ref id="B30"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dato</surname> <given-names>A.</given-names></name> <name><surname>Radmilovic</surname> <given-names>V.</given-names></name> <name><surname>Lee</surname> <given-names>Z.</given-names></name> <name><surname>Phillips</surname> <given-names>J.</given-names></name> <name><surname>Frenklach</surname> <given-names>M.</given-names></name></person-group> (<year>2008</year>). <article-title>Substrate-free gas-phase synthesis of graphene sheets</article-title>. <source>Nano Lett.</source> <volume>8</volume>, <fpage>2012</fpage>&#x02013;<lpage>2016</lpage>.<pub-id pub-id-type="doi">10.1021/nl8011566</pub-id><pub-id pub-id-type="pmid">18529034</pub-id></citation></ref>
<ref id="B190"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Damjanovic</surname> <given-names>D.</given-names></name> <name><surname>Newnham</surname> <given-names>R. E.</given-names></name></person-group> (<year>1992</year>). <article-title>Electrostrictive and piezoelectric materials for actuator applications</article-title>. <source>J. Int. Mat. Sys. Struct.</source> <volume>3</volume>, <fpage>190</fpage>&#x02013;<lpage>208</lpage>.<pub-id pub-id-type="doi">10.1177/1045389X9200300201</pub-id></citation></ref>
<ref id="B31"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dean</surname> <given-names>C. R.</given-names></name> <name><surname>Young</surname> <given-names>A. F.</given-names></name> <name><surname>Meric</surname> <given-names>I.</given-names></name> <name><surname>Lee</surname> <given-names>C.</given-names></name> <name><surname>Wang</surname> <given-names>L.</given-names></name> <name><surname>Sorgenfrei</surname> <given-names>S.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Boron nitride substrates for high-quality graphene electronics</article-title>. <source>Nat. Nanotechnol.</source> <volume>5</volume>, <fpage>722</fpage>&#x02013;<lpage>726</lpage>.<pub-id pub-id-type="doi">10.1038/nnano.2010.172</pub-id><pub-id pub-id-type="pmid">20729834</pub-id></citation></ref>
<ref id="B32"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dijkkamp</surname> <given-names>D.</given-names></name> <name><surname>Venkatesan</surname> <given-names>T.</given-names></name> <name><surname>Wu</surname> <given-names>X. D.</given-names></name> <name><surname>Shaheen</surname> <given-names>S. A.</given-names></name> <name><surname>Jisrawi</surname> <given-names>N.</given-names></name> <name><surname>Min-Lee</surname> <given-names>Y. H.</given-names></name> <etal/></person-group> (<year>1987</year>). <article-title>Preparation of Y-Ba-Cu oxide superconductor thin films using pulsed laser evaporation from high Tc bulk materials</article-title>. <source>Appl. Phys. Lett.</source> <volume>51</volume>, <fpage>619</fpage>.<pub-id pub-id-type="doi">10.1063/1.98366</pub-id></citation></ref>
<ref id="B33"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dong</surname> <given-names>J.</given-names></name> <name><surname>Ding</surname> <given-names>J.</given-names></name> <name><surname>Weng</surname> <given-names>J.</given-names></name> <name><surname>Dai</surname> <given-names>L.</given-names></name></person-group> (<year>2013</year>). <article-title>Graphene enhances the shape memory of poly (acrylamide-co-acrylic acid) grafted on graphene</article-title>. <source>Macromol. Rapid Commun.</source> <volume>34</volume>, <fpage>659</fpage>&#x02013;<lpage>664</lpage>.<pub-id pub-id-type="doi">10.1002/marc.201200814</pub-id><pub-id pub-id-type="pmid">23585125</pub-id></citation></ref>
<ref id="B34"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dreyer</surname> <given-names>D. R.</given-names></name> <name><surname>Park</surname> <given-names>S.</given-names></name> <name><surname>Bielawski</surname> <given-names>C. W.</given-names></name> <name><surname>Ruoff</surname> <given-names>R. S.</given-names></name></person-group> (<year>2010</year>). <article-title>The chemistry of graphene oxide</article-title>. <source>Chem. Soc. Rev.</source> <volume>39</volume>, <fpage>228</fpage>&#x02013;<lpage>240</lpage>.<pub-id pub-id-type="doi">10.1039/b917103g</pub-id><pub-id pub-id-type="pmid">20023850</pub-id></citation></ref>
<ref id="B35"><citation citation-type="book"><person-group person-group-type="author"><name><surname>Eason</surname> <given-names>R.</given-names></name></person-group> (<year>2006</year>). <source>Pulsed Laser Deposition of Thin Films: Applications-Led Growth of Functional materials</source>. <publisher-loc>Hoboken, NJ</publisher-loc>: <publisher-name>John Wiley &#x00026; Sons, Inc</publisher-name>.</citation></ref>
<ref id="B36"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Elias</surname> <given-names>D. C.</given-names></name> <name><surname>Nair</surname> <given-names>R. R.</given-names></name> <name><surname>Mohiuddin</surname> <given-names>T. M.</given-names></name> <name><surname>Morozov</surname> <given-names>S. V.</given-names></name> <name><surname>Blake</surname> <given-names>P.</given-names></name> <name><surname>Halsall</surname> <given-names>M. P.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Control of graphene&#x02019;s properties by reversible hydrogenation: evidence for graphane</article-title>. <source>Science</source> <volume>323</volume>, <fpage>610</fpage>&#x02013;<lpage>613</lpage>.<pub-id pub-id-type="doi">10.1126/science.1167130</pub-id><pub-id pub-id-type="pmid">19179524</pub-id></citation></ref>
<ref id="B37"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Eroms</surname> <given-names>J.</given-names></name> <name><surname>Weiss</surname> <given-names>D.</given-names></name></person-group> (<year>2009</year>). <article-title>Weak localization and transport gap in graphene antidot lattices</article-title>. <source>New J. Phys.</source> <volume>11</volume>, <fpage>095021</fpage>.<pub-id pub-id-type="doi">10.1088/1367-2630/11/9/095021</pub-id></citation></ref>
<ref id="B38"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Fogarassy</surname> <given-names>E.</given-names></name> <name><surname>Fuchs</surname> <given-names>C.</given-names></name> <name><surname>Slaoui</surname> <given-names>A.</given-names></name> <name><surname>Stoquert</surname> <given-names>J. P.</given-names></name></person-group> (<year>1990</year>). <article-title>SiO2 thin-film deposition by excimer laser ablation from SiO target in oxygen atmosphere</article-title>. <source>Appl. Phys. Lett.</source> <volume>57</volume>, <fpage>664</fpage>&#x02013;<lpage>666</lpage>.<pub-id pub-id-type="doi">10.1063/1.104253</pub-id></citation></ref>
<ref id="B39"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Foster</surname> <given-names>C. M.</given-names></name> <name><surname>Voss</surname> <given-names>K. F.</given-names></name> <name><surname>Hagler</surname> <given-names>T. W.</given-names></name> <name><surname>Mihailovi</surname> <given-names>D.</given-names></name> <name><surname>Heeger</surname> <given-names>A. J.</given-names></name> <name><surname>Eddy</surname> <given-names>M. M.</given-names></name> <etal/></person-group> (<year>1990</year>). <article-title>Infrared reflection of epitaxial Tl2Ba2CaCu2O8 thin films in the normal and superconducting states</article-title>. <source>Solid State Commun.</source> <volume>76</volume>, <fpage>651</fpage>.<pub-id pub-id-type="doi">10.1016/0038-1098(90)90108-N</pub-id></citation></ref>
<ref id="B40"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Geim</surname> <given-names>A. K.</given-names></name></person-group> (<year>2009</year>). <article-title>Graphene: status and prospects</article-title>. <source>Science</source> <volume>324</volume>, <fpage>1530</fpage>&#x02013;<lpage>1534</lpage>.<pub-id pub-id-type="doi">10.1126/science.1158877</pub-id><pub-id pub-id-type="pmid">19541989</pub-id></citation></ref>
<ref id="B41"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Geim</surname> <given-names>A. K.</given-names></name> <name><surname>Novoselov</surname> <given-names>K. S.</given-names></name></person-group> (<year>2007a</year>). <article-title>The rise of graphene</article-title>. <source>Nat. Mater.</source> <volume>6</volume>, <fpage>183</fpage>&#x02013;<lpage>191</lpage>.<pub-id pub-id-type="doi">10.1038/nmat1849</pub-id><pub-id pub-id-type="pmid">17330084</pub-id></citation></ref>
<ref id="B42"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Geim</surname> <given-names>A. K.</given-names></name> <name><surname>Novoselov</surname> <given-names>K. S.</given-names></name></person-group> (<year>2007b</year>). <article-title>The rise of graphene</article-title>. <source>Nat. Mater.</source> <volume>6</volume>, <fpage>183</fpage>&#x02013;<lpage>191</lpage>.<pub-id pub-id-type="doi">10.1038/nmat1849</pub-id><pub-id pub-id-type="pmid">17330084</pub-id></citation></ref>
<ref id="B43"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Geurtsen</surname> <given-names>A. J. M.</given-names></name> <name><surname>Kools</surname> <given-names>J.C.S.</given-names></name> <name><surname>Wit</surname> <given-names>L.</given-names></name> <name><surname>Lodde</surname> <given-names>J.C.</given-names></name></person-group> (<year>1996</year>). <article-title>Pulsed laser deposition of permanent magnetic Nd2Fe14B thin films</article-title>. <source>Appl. Surf. Sci.</source> <volume>9698</volume>, <fpage>887</fpage>&#x02013;<lpage>890</lpage>.<pub-id pub-id-type="doi">10.1016/0169-4332(95)00541-2</pub-id></citation></ref>
<ref id="B44"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ghosh</surname> <given-names>S.</given-names></name> <name><surname>Bao</surname> <given-names>W.</given-names></name> <name><surname>Nika</surname> <given-names>D. L.</given-names></name> <name><surname>Subrina</surname> <given-names>S.</given-names></name> <name><surname>Pokatilov</surname> <given-names>E. P.</given-names></name> <name><surname>Lau</surname> <given-names>C. N.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Dimensional crossover of thermal transport in few-layer graphene</article-title>. <source>Nat. Mater.</source> <volume>9</volume>, <fpage>555</fpage>&#x02013;<lpage>558</lpage>.<pub-id pub-id-type="doi">10.1038/nmat2753</pub-id><pub-id pub-id-type="pmid">20453845</pub-id></citation></ref>
<ref id="B45"><citation citation-type="book"><person-group person-group-type="author"><name><surname>Giannazzo</surname> <given-names>F.</given-names></name> <name><surname>Raineri</surname> <given-names>V.</given-names></name> <name><surname>Rimini</surname> <given-names>E.</given-names></name></person-group> (<year>2011</year>). <article-title>&#x0201C;Transport properties of graphene with nanoscale lateral resolution,&#x0201D;</article-title> in <source>Scanning Probe Microscopy in Nanoscience and Nanotechnology 2</source>, ed. <person-group person-group-type="editor"><name><surname>Bhushan</surname> <given-names>B.</given-names></name></person-group> (<publisher-loc>Berlin</publisher-loc>: <publisher-name>Springer</publisher-name>), <fpage>247</fpage>&#x02013;<lpage>285</lpage>.</citation></ref>
<ref id="B46"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Gomez De Arco</surname> <given-names>L.</given-names></name></person-group> (<year>2010</year>). <article-title>Continuous, highly flexible, and transparent graphene films by chemical vapor deposition for organic photovoltaics</article-title>. <source>ACS Nano</source> <volume>4</volume>, <fpage>2865</fpage>&#x02013;<lpage>2873</lpage>.<pub-id pub-id-type="doi">10.1021/nn901587x</pub-id><pub-id pub-id-type="pmid">20394355</pub-id></citation></ref>
<ref id="B47"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>G&#x000F3;mez-Navarro</surname> <given-names>C.</given-names></name> <name><surname>Burghard</surname> <given-names>M.</given-names></name> <name><surname>Kern</surname> <given-names>K.</given-names></name></person-group> (<year>2008</year>). <article-title>Elastic properties of chemically derived single graphene sheets</article-title>. <source>Nano Lett.</source> <volume>8</volume>, <fpage>2045</fpage>&#x02013;<lpage>2049</lpage>.<pub-id pub-id-type="doi">10.1021/nl801384y</pub-id><pub-id pub-id-type="pmid">18540659</pub-id></citation></ref>
<ref id="B48"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Green</surname> <given-names>A. A.</given-names></name> <name><surname>Hersam</surname> <given-names>M. C.</given-names></name></person-group> (<year>2009</year>). <article-title>Solution phase production of graphene with controlled thickness via density differentiation</article-title>. <source>Nano Lett.</source> <volume>9</volume>, <fpage>4031</fpage>&#x02013;<lpage>4036</lpage>.<pub-id pub-id-type="doi">10.1021/nl902200b</pub-id><pub-id pub-id-type="pmid">19780528</pub-id></citation></ref>
<ref id="B49"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Guermoune</surname> <given-names>A.</given-names></name> <name><surname>Chari</surname> <given-names>T.</given-names></name> <name><surname>Popescu</surname> <given-names>F.</given-names></name> <name><surname>Sabri</surname> <given-names>S. S.</given-names></name> <name><surname>Guillemette</surname> <given-names>J.</given-names></name> <name><surname>Skulason</surname> <given-names>H. S.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Chemical vapor deposition synthesis of graphene on copper with methanol, ethanol, and propanol precursors</article-title>. <source>Carbon</source> <volume>49</volume>, <fpage>4204</fpage>&#x02013;<lpage>4210</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2011.05.054</pub-id></citation></ref>
<ref id="B50"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Guinea</surname> <given-names>F.</given-names></name> <name><surname>Katsnelson</surname> <given-names>M. I.</given-names></name> <name><surname>Geim</surname> <given-names>A. K.</given-names></name></person-group> (<year>2010</year>). <article-title>Energy gaps and a zero-field quantum Hall effect in graphene by strain engineering</article-title>. <source>Nat. Phys.</source> <volume>6</volume>, <fpage>30</fpage>&#x02013;<lpage>33</lpage>.<pub-id pub-id-type="doi">10.1038/nphys1420</pub-id></citation></ref>
<ref id="B51"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Gunst</surname> <given-names>T.</given-names></name> <name><surname>Markussen</surname> <given-names>T.</given-names></name> <name><surname>Jauho</surname> <given-names>A.-P.</given-names></name> <name><surname>Brandbyge</surname> <given-names>M.</given-names></name></person-group> (<year>2011</year>). <article-title>Thermoelectric properties of finite graphene antidot lattices</article-title>. <source>Phys. Rev. B</source> <volume>84</volume>, <fpage>155449</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.84.155449</pub-id></citation></ref>
<ref id="B52"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Guo</surname> <given-names>C. X.</given-names></name> <name><surname>Guai</surname> <given-names>G. H.</given-names></name> <name><surname>Ming</surname> <given-names>C.</given-names></name></person-group> (<year>2011</year>). <article-title>Graphene based materials: enhancing solar energy harvesting</article-title>. <source>Adv. Energy Mater.</source> <volume>1</volume>, <fpage>448</fpage>&#x02013;<lpage>452</lpage>.<pub-id pub-id-type="doi">10.1002/aenm.201100119</pub-id></citation></ref>
<ref id="B54"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Han</surname> <given-names>S.</given-names></name> <name><surname>Chun</surname> <given-names>B. C.</given-names></name></person-group> (<year>2014</year>). <article-title>Preparation of polyurethane nanocomposites via covalent incorporation of functionalized graphene and its shape memory effect</article-title>. <source>Compos. Part A. Appl. Sci. Manuf.</source> <volume>58</volume>, <fpage>65</fpage>&#x02013;<lpage>72</lpage>.<pub-id pub-id-type="doi">10.1016/j.compositesa.2013.11.016</pub-id></citation></ref>
<ref id="B55"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hansen</surname> <given-names>S. G.</given-names></name> <name><surname>Robitaille</surname> <given-names>T. E.</given-names></name></person-group> (<year>1988</year>). <article-title>Formation of polymer films by pulsed laser evaporation</article-title>. <source>Appl. Phys. Lett.</source> <volume>52</volume>, <fpage>81</fpage>&#x02013;<lpage>83</lpage>.<pub-id pub-id-type="doi">10.1063/1.99332</pub-id></citation></ref>
<ref id="B56"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Haskins</surname> <given-names>J.</given-names></name> <name><surname>K&#x00131;nac&#x00131;</surname> <given-names>A.</given-names></name> <name><surname>Sevik</surname> <given-names>C.</given-names></name> <name><surname>Sevin&#x000E7;li</surname> <given-names>H.</given-names></name> <name><surname>Cuniberti</surname> <given-names>G.</given-names></name> <name><surname>Ca&#x0011F;&#x00131;n</surname> <given-names>T.</given-names></name></person-group> (<year>2009</year>). <article-title>A theoretical study on thermoelectric properties of graphene nanoribbons</article-title>. <source>Appl. Phys. Lett.</source> <volume>94</volume>, <fpage>263107</fpage>.<pub-id pub-id-type="doi">10.1021/nn200114p</pub-id><pub-id pub-id-type="pmid">21452884</pub-id></citation></ref>
<ref id="B57"><citation citation-type="book"><person-group person-group-type="editor"><name><surname>Hassan</surname> <given-names>R.</given-names></name></person-group> (ed.) (<year>2012</year>). <article-title>&#x0201C;Graphene nanoelectronics,&#x0201D;</article-title> in <source>Metrology, Synthesis Properties and Applications</source> (<publisher-loc>Berlin</publisher-loc>: <publisher-name>Springer-Verlag</publisher-name>), <fpage>598</fpage>.</citation></ref>
<ref id="B58"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>He</surname> <given-names>Z.</given-names></name> <name><surname>Zhong</surname> <given-names>C.</given-names></name> <name><surname>Huang</surname> <given-names>X.</given-names></name> <name><surname>Wong</surname> <given-names>W.-Y.</given-names></name> <name><surname>Wu</surname> <given-names>H.</given-names></name> <name><surname>Chen</surname> <given-names>L.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Simultaneous enhancement of open-circuit voltage, short-circuit current density, and fill factor in polymer solar cells</article-title>. <source>Adv. Mater. Weinheim</source> <volume>23</volume>, <fpage>4636</fpage>&#x02013;<lpage>4643</lpage>.<pub-id pub-id-type="doi">10.1002/adma.201103006</pub-id></citation></ref>
<ref id="B59"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hernandez</surname> <given-names>Y.</given-names></name> <name><surname>Nicolosi</surname> <given-names>V.</given-names></name> <name><surname>Lotya</surname> <given-names>M.</given-names></name> <name><surname>Blighe</surname> <given-names>F. M.</given-names></name> <name><surname>Sun</surname> <given-names>Z.</given-names></name> <name><surname>De</surname> <given-names>S.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>High-yield production of graphene by liquid-phase exfoliation of graphite</article-title>. <source>Nat. Nanotechnol.</source> <volume>3</volume>, <fpage>563</fpage>&#x02013;<lpage>568</lpage>.<pub-id pub-id-type="doi">10.1038/nnano.2008.215</pub-id><pub-id pub-id-type="pmid">18772919</pub-id></citation></ref>
<ref id="B60"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hone</surname> <given-names>J.</given-names></name> <name><surname>Ellwood</surname> <given-names>I.</given-names></name> <name><surname>Muno</surname> <given-names>M.</given-names></name> <name><surname>Mizel</surname> <given-names>A.</given-names></name> <name><surname>Cohen</surname> <given-names>M. L.</given-names></name> <name><surname>Zettl</surname> <given-names>A.</given-names></name> <etal/></person-group> (<year>1998</year>). <article-title>Thermoelectric power of single-walled carbon nanotubes</article-title>. <source>Phys. Rev. Lett.</source> <volume>80</volume>, <fpage>1042</fpage>&#x02013;<lpage>1045</lpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.80.1042</pub-id></citation></ref>
<ref id="B61"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Houssa</surname> <given-names>M.</given-names></name> <name><surname>Pourtois</surname> <given-names>G.</given-names></name> <name><surname>Afanas&#x02019;ev</surname> <given-names>V. V.</given-names></name> <name><surname>Stesmans</surname> <given-names>A.</given-names></name></person-group> (<year>2010</year>). <article-title>Electronic properties of two-dimensional hexagonal germanium</article-title>. <source>Appl. Phys. Lett.</source> <volume>96</volume>, <fpage>082111</fpage>.<pub-id pub-id-type="doi">10.1063/1.3332588</pub-id></citation></ref>
<ref id="B63"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Huang</surname> <given-names>L.</given-names></name> <name><surname>Yi</surname> <given-names>N.</given-names></name> <name><surname>Wu</surname> <given-names>Y.</given-names></name> <name><surname>Zhang</surname> <given-names>Y.</given-names></name> <name><surname>Zhang</surname> <given-names>Q.</given-names></name> <name><surname>Huang</surname> <given-names>Y.</given-names></name> <etal/></person-group> (<year>2013</year>). <article-title>Multichannel and repeatable self-healing of mechanical enhanced grapheme-thermoplastic polyurethane composites</article-title>. <source>Adv. Mater. Weinheim</source> <volume>25</volume>, <fpage>2224</fpage>&#x02013;<lpage>2228</lpage>.<pub-id pub-id-type="doi">10.1002/adma.201204768</pub-id><pub-id pub-id-type="pmid">23417742</pub-id></citation></ref>
<ref id="B64"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Huang</surname> <given-names>W.</given-names></name> <name><surname>Wang</surname> <given-names>J.-S.</given-names></name> <name><surname>Liang</surname> <given-names>G.</given-names></name></person-group> (<year>2011</year>). <article-title>Theoretical study on thermoelectric properties of kinked graphene nanoribbons</article-title>. <source>Phys. Rev. B</source> <volume>84</volume>, <fpage>045410</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.84.045410</pub-id></citation></ref>
<ref id="B65"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Inoue</surname> <given-names>K.</given-names></name> <name><surname>Yanagisawa</surname> <given-names>R.</given-names></name> <name><surname>Koike</surname> <given-names>E.</given-names></name> <name><surname>Nishikawa</surname> <given-names>M.</given-names></name> <name><surname>Takano</surname> <given-names>H.</given-names></name></person-group> (<year>2010</year>). <article-title>Combustion synthesis of carbon nanotubes and related nanostructures</article-title>. <source>Prog. Energy Combust. Sci.</source> <volume>36</volume>, <fpage>696</fpage>&#x02013;<lpage>727</lpage>.<pub-id pub-id-type="doi">10.1016/j.freeradbiomed.2010.01.013</pub-id><pub-id pub-id-type="pmid">20093178</pub-id></citation></ref>
<ref id="B66"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ji</surname> <given-names>Y.</given-names></name> <name><surname>Lee</surname> <given-names>S.</given-names></name> <name><surname>Cho</surname> <given-names>B.</given-names></name> <name><surname>Song</surname> <given-names>S.</given-names></name> <name><surname>Lee</surname> <given-names>T.</given-names></name></person-group> (<year>2011</year>). <article-title>Flexible organic memory devices with multilayer graphene electrodes</article-title>. <source>ACS Nano</source> <volume>5</volume>, <fpage>5995</fpage>&#x02013;<lpage>6000</lpage>.<pub-id pub-id-type="doi">10.1021/nn201770s</pub-id><pub-id pub-id-type="pmid">21662978</pub-id></citation></ref>
<ref id="B67"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Jo</surname> <given-names>G.</given-names></name> <name><surname>Na</surname> <given-names>S.-I.</given-names></name> <name><surname>Oh</surname> <given-names>S.-H.</given-names></name> <name><surname>Lee</surname> <given-names>S.</given-names></name> <name><surname>Kim</surname> <given-names>T.-S.</given-names></name> <name><surname>Wang</surname> <given-names>G.</given-names></name> <etal/></person-group> (<year>2012</year>). <article-title>The application of graphene as electrodes in electrical and optical devices</article-title>. <source>Nanotechnology</source> <volume>23</volume>, <fpage>112001</fpage>.<pub-id pub-id-type="doi">10.1088/0957-4484/23/11/112001</pub-id><pub-id pub-id-type="pmid">22370228</pub-id></citation></ref>
<ref id="B68"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Jo</surname> <given-names>G.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Tuning of a graphene-electrode work function to enhance the efficiency of organic bulk heterojunction photovoltaic cells with an inverted structure</article-title>. <source>Appl. Phys. Lett.</source> <volume>97</volume>, <fpage>213301</fpage>.<pub-id pub-id-type="doi">10.1063/1.3514551</pub-id></citation></ref>
<ref id="B69"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kammler</surname> <given-names>H. K.</given-names></name> <name><surname>M&#x000E4;er</surname> <given-names>L.</given-names></name> <name><surname>Pratsinis</surname> <given-names>S. E.</given-names></name></person-group> (<year>2001</year>). <article-title>Flame synthesis of nanoparticles</article-title>. <source>Chem. Eng. Technol.</source> <volume>24</volume>, <fpage>583</fpage>&#x02013;<lpage>596</lpage>.<pub-id pub-id-type="doi">10.1002/1521-4125(200106)24:6&#x0003C;583::AID-CEAT583&#x0003E;3.0.CO;2-H</pub-id></citation></ref>
<ref id="B71"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Karamitaheri</surname> <given-names>H.</given-names></name> <name><surname>Pourfath</surname> <given-names>M.</given-names></name> <name><surname>Faez</surname> <given-names>R.</given-names></name> <name><surname>Kosina</surname> <given-names>H.</given-names></name></person-group> (<year>2011</year>). <article-title>Geometrical effects on the thermoelectric properties of ballistic graphene antidot lattices</article-title>. <source>J. Appl. Phys.</source> <volume>110</volume>, <fpage>054506</fpage>.<pub-id pub-id-type="doi">10.1063/1.3629990</pub-id></citation></ref>
<ref id="B72"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kellie</surname> <given-names>B. M.</given-names></name> <name><surname>Silleck</surname> <given-names>A. C.</given-names></name> <name><surname>Bellman</surname> <given-names>K.</given-names></name> <name><surname>Snodgrass</surname> <given-names>R.</given-names></name> <name><surname>Prakash</surname> <given-names>S.</given-names></name></person-group> (<year>2013</year>). <article-title>Deposition of few-layered graphene in a microcombustor on copper and nickel substrates</article-title>. <source>RSC Adv.</source> <volume>3</volume>, <fpage>7100</fpage>&#x02013;<lpage>7105</lpage>.<pub-id pub-id-type="doi">10.1039/c3ra40632f</pub-id></citation></ref>
<ref id="B53"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kerbs</surname> <given-names>H. U.</given-names></name> <name><surname>Bremert</surname> <given-names>O.</given-names></name></person-group> (<year>1993</year>). <article-title>Pulsed-laser deposition of thin metallic alloys</article-title>. <source>Appl. Phys. Lett.</source> <volume>62</volume>, <fpage>2341</fpage>.<pub-id pub-id-type="doi">10.1021/am3022976</pub-id><pub-id pub-id-type="pmid">23206317</pub-id></citation></ref>
<ref id="B73"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kidoh</surname> <given-names>H.</given-names></name> <name><surname>Ogawa</surname> <given-names>T.</given-names></name> <name><surname>Morimoto</surname> <given-names>A.</given-names></name> <name><surname>Shimizu</surname> <given-names>T.</given-names></name></person-group> (<year>1991</year>). <article-title>Ferroelectric properties of lead-zirconate-titanate films prepared by laser ablation</article-title>. <source>Appl. Phys. Lett.</source> <volume>58</volume>, <fpage>2910</fpage>.<pub-id pub-id-type="doi">10.1063/1.104719</pub-id></citation></ref>
<ref id="B74"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname> <given-names>J.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Low-temperature synthesis of large-area graphene-based transparent conductive films using surface wave plasma chemical vapor deposition</article-title>. <source>Appl. Phys. Lett.</source> <volume>98</volume>, <fpage>091502</fpage>.<pub-id pub-id-type="doi">10.1063/1.3561747</pub-id></citation></ref>
<ref id="B75"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname> <given-names>J.T.</given-names></name> <name><surname>Kim</surname> <given-names>B.K.</given-names></name> <name><surname>Kim</surname> <given-names>E.Y.</given-names></name> <name><surname>Park</surname> <given-names>H.C.</given-names></name> <name><surname>Jeong</surname> <given-names>H.M.</given-names></name></person-group> (<year>2014</year>). <article-title>Synthesis and shape memory performance of polyurethane/graphene nanocomposites</article-title>. <source>React. Funct. Polym.</source> <volume>74</volume>, <fpage>16</fpage>&#x02013;<lpage>21</lpage>.<pub-id pub-id-type="doi">10.1016/j.reactfunctpolym.2013.10.004</pub-id></citation></ref>
<ref id="B76"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname> <given-names>K. S.</given-names></name> <name><surname>Zhao</surname> <given-names>Y.</given-names></name> <name><surname>Jang</surname> <given-names>H.</given-names></name> <name><surname>Lee</surname> <given-names>S. Y.</given-names></name> <name><surname>Kim</surname> <given-names>J. M.</given-names></name> <name><surname>Kim</surname> <given-names>K. S.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Large-scale pattern growth of graphene films for stretchable transparent electrodes</article-title>. <source>Nature</source> <volume>457</volume>, <fpage>706</fpage>&#x02013;<lpage>710</lpage>.<pub-id pub-id-type="doi">10.1038/nature07719</pub-id><pub-id pub-id-type="pmid">19145232</pub-id></citation></ref>
<ref id="B77"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname> <given-names>M.</given-names></name> <name><surname>Safron</surname> <given-names>N. S.</given-names></name> <name><surname>Han</surname> <given-names>E.</given-names></name> <name><surname>Arnold</surname> <given-names>M. S.</given-names></name> <name><surname>Gopalan</surname> <given-names>P.</given-names></name></person-group> (<year>2010</year>). <article-title>Fabrication and characterization of large-area, semiconducting nanoperforated graphene materials</article-title>. <source>Nano Lett.</source> <volume>10</volume>, <fpage>1125</fpage>&#x02013;<lpage>1131</lpage>.<pub-id pub-id-type="doi">10.1021/nl9032318</pub-id><pub-id pub-id-type="pmid">20192229</pub-id></citation></ref>
<ref id="B78"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Koh</surname> <given-names>A. T. T.</given-names></name> <name><surname>Foong</surname> <given-names>Y. M.</given-names></name> <name><surname>Chua</surname> <given-names>D. H. C.</given-names></name></person-group> (<year>2010</year>). <article-title>Cooling rate and energy dependence of pulsed laser fabricated graphene on nickel at reduced temperature</article-title>. <source>Appl. Phys. Lett.</source> <volume>97</volume>, <fpage>114102</fpage>.<pub-id pub-id-type="doi">10.1063/1.3489993</pub-id></citation></ref>
<ref id="B79"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Krebs</surname> <given-names>H. U.</given-names></name> <name><surname>Weisheit</surname> <given-names>M.</given-names></name> <name><surname>Faupel</surname> <given-names>J.</given-names></name> <name><surname>S&#x000FC;ske</surname> <given-names>E.</given-names></name> <name><surname>Scharf</surname> <given-names>T.</given-names></name> <name><surname>Fuhse</surname> <given-names>C.</given-names></name> <etal/></person-group> (<year>2003</year>). <article-title>Pulsed laser deposition (PLD), a versatile thin film technique</article-title>. <source>Adv. Solid State Phys.</source> <fpage>505</fpage>&#x02013;<lpage>518</lpage>.<pub-id pub-id-type="doi">10.1007/978-3-540-44838-9_36</pub-id></citation></ref>
<ref id="B80"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Krivchenko</surname> <given-names>V.A.</given-names></name> <name><surname>Dvorkin</surname> <given-names>V.V.</given-names></name> <name><surname>Dzbanovsky</surname> <given-names>N.N.</given-names></name> <name><surname>Timofeyev</surname> <given-names>M.A.</given-names></name> <name><surname>Stepanov</surname> <given-names>A.S.</given-names></name> <name><surname>Rakhimov</surname> <given-names>A.T.</given-names></name> <etal/></person-group> (<year>2012</year>). <article-title>Evolution of carbon film structure during its catalyst-free growth in the plasma of direct current glow discharge</article-title>. <source>Carbon N. Y.</source> <volume>50</volume>, <fpage>1477</fpage>&#x02013;<lpage>1487</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2011.11.018</pub-id></citation></ref>
<ref id="B81"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kuribayashi</surname> <given-names>K.</given-names></name> <etal/></person-group> (<year>1989</year>). <article-title>Millimeter-sized joint actuator using a shape memory alloy</article-title>. <source>Sens. Actuators</source> <volume>20</volume>, <fpage>57</fpage>&#x02013;<lpage>64</lpage>.<pub-id pub-id-type="doi">10.1016/0250-6874(89)87102-1</pub-id></citation></ref>
<ref id="B82"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Layek</surname> <given-names>R. K.</given-names></name> <name><surname>Nandi</surname> <given-names>A. K.</given-names></name></person-group> (<year>2013</year>). <article-title>A review on synthesis and properties of polymer functionalized graphene</article-title>. <source>Polymer</source> <volume>54</volume>, <fpage>5087</fpage>&#x02013;<lpage>5103</lpage>.<pub-id pub-id-type="doi">10.1016/j.polymer.2013.06.027</pub-id></citation></ref>
<ref id="B83"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Lee</surname> <given-names>C.</given-names></name> <name><surname>Wei</surname> <given-names>X.</given-names></name> <name><surname>Kysar</surname> <given-names>J. W.</given-names></name> <name><surname>Hone</surname> <given-names>J.</given-names></name></person-group> (<year>2008</year>). <article-title>Measurement of the elastic properties and intrinsic strength of monolayer graphene</article-title>. <source>Science</source> <volume>321</volume>, <fpage>385</fpage>&#x02013;<lpage>388</lpage>.<pub-id pub-id-type="doi">10.1126/science.1157996</pub-id><pub-id pub-id-type="pmid">18635798</pub-id></citation></ref>
<ref id="B84"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Lee</surname> <given-names>S.K.</given-names></name> <name><surname>Kim</surname> <given-names>B.K.</given-names></name></person-group> (<year>2014</year>). <article-title>Synthesis and properties of shape memory graphene oxide/polyurethane chemical hybrids</article-title>. <source>Polym. Int.</source> <volume>63</volume>, <fpage>1197</fpage>&#x02013;<lpage>1202</lpage>.<pub-id pub-id-type="doi">10.1002/pi.4617</pub-id></citation></ref>
<ref id="B85"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Lee</surname> <given-names>W. H.</given-names></name> <name><surname>Park</surname> <given-names>J.</given-names></name> <name><surname>Sim</surname> <given-names>S. H.</given-names></name> <name><surname>Jo</surname> <given-names>S. B.</given-names></name> <name><surname>Kim</surname> <given-names>K. S.</given-names></name> <name><surname>Hong</surname> <given-names>B. H.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Transparent flexible organic transistors based on monolayer graphene electrodes on plastic</article-title>. <source>Adv. Mater. Weinheim</source> <volume>23</volume>, <fpage>1752</fpage>&#x02013;<lpage>1756</lpage>.<pub-id pub-id-type="doi">10.1002/adma.201004099</pub-id></citation></ref>
<ref id="B86"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>J. F.</given-names></name> <etal/></person-group> (<year>2010d</year>). <article-title>High-performance nanostructured thermoelectric materials</article-title>. <source>NPG Asia Mater.</source> <volume>2</volume>, <fpage>152</fpage>&#x02013;<lpage>158</lpage>.<pub-id pub-id-type="doi">10.1038/asiamat.2010.138</pub-id></citation></ref>
<ref id="B87"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>L.</given-names></name> <etal/></person-group> (<year>2015</year>). <article-title>Graphene oxide vs. reduced graphene oxide as core substrate for core/shell-structured dielectric nanoplates with different electro-responsive characteristics</article-title>. <source>J. Mater. Chem. C</source> <volume>3</volume>, <fpage>5098</fpage>&#x02013;<lpage>5108</lpage>.<pub-id pub-id-type="doi">10.1039/C5TC00474H</pub-id></citation></ref>
<ref id="B88"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>S. S.</given-names></name> <name><surname>Tu</surname> <given-names>K. H.</given-names></name> <name><surname>Lin</surname> <given-names>C. C.</given-names></name> <name><surname>Chen</surname> <given-names>C. W.</given-names></name> <name><surname>Chhowalla</surname> <given-names>M.</given-names></name></person-group> (<year>2010b</year>). <article-title>Solution-processable graphene oxide as an efficient hole transport layer in polymer solar cells</article-title>. <source>ACS Nano</source> <volume>4</volume>, <fpage>3169</fpage>&#x02013;<lpage>3174</lpage>.<pub-id pub-id-type="doi">10.1021/nn100551j</pub-id><pub-id pub-id-type="pmid">20481512</pub-id></citation></ref>
<ref id="B89"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>X.</given-names></name> <name><surname>Zhu</surname> <given-names>H.</given-names></name> <name><surname>Wang</surname> <given-names>K.</given-names></name> <name><surname>Cao</surname> <given-names>A.</given-names></name> <name><surname>Wei</surname> <given-names>J.</given-names></name> <name><surname>Li</surname> <given-names>C.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Large-area synthesis of high-quality and uniform graphene films on copper foils</article-title>. <source>Science</source> <volume>324</volume>, <fpage>1312</fpage>&#x02013;<lpage>1314</lpage>.<pub-id pub-id-type="doi">10.1126/science.1171245</pub-id><pub-id pub-id-type="pmid">19423775</pub-id></citation></ref>
<ref id="B90"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>X.</given-names></name> <etal/></person-group> (<year>2010c</year>). <article-title>Graphene-on-silicon Schottky junction solar cells</article-title>. <source>Adv. Mater. Weinheim</source> <volume>22</volume>, <fpage>2743</fpage>&#x02013;<lpage>2748</lpage>.<pub-id pub-id-type="doi">10.1002/adma.200904383</pub-id></citation></ref>
<ref id="B91"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>X.</given-names></name> <name><surname>Zhu</surname> <given-names>H.</given-names></name> <name><surname>Wang</surname> <given-names>K.</given-names></name> <name><surname>Cao</surname> <given-names>A.</given-names></name> <name><surname>Wei</surname> <given-names>J.</given-names></name> <name><surname>Li</surname> <given-names>C.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Chemically derived, ultrasmooth graphene nanoribbon semiconductors</article-title>. <source>Science</source> <volume>319</volume>, <fpage>1229</fpage>&#x02013;<lpage>1232</lpage>.<pub-id pub-id-type="doi">10.1126/science.1150878</pub-id><pub-id pub-id-type="pmid">18218865</pub-id></citation></ref>
<ref id="B92"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>X.</given-names></name> <name><surname>Zhu</surname> <given-names>H.</given-names></name> <name><surname>Wang</surname> <given-names>K.</given-names></name> <name><surname>Cao</surname> <given-names>A.</given-names></name> <name><surname>Wei</surname> <given-names>J.</given-names></name> <name><surname>Li</surname> <given-names>C.</given-names></name> <etal/></person-group> (<year>2010a</year>). <article-title>Graphene-on-silicon Schottky junction solar cells</article-title>. <source>Adv. Mater.</source> <volume>22</volume>, <fpage>2743</fpage>.<pub-id pub-id-type="doi">10.1002/adma.200904383</pub-id></citation></ref>
<ref id="B93"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>J.-F.</given-names></name> <name><surname>Liu</surname> <given-names>W.-S.</given-names></name> <name><surname>Zhao</surname> <given-names>L.-D.</given-names></name> <name><surname>Zhou</surname> <given-names>M.</given-names></name> <etal/></person-group> (<year>2011a</year>). <article-title>Ethanol flame synthesis of highly transparent carbon thin films</article-title>. <source>Carbon N. Y.</source> <volume>49</volume>, <fpage>237</fpage>&#x02013;<lpage>241</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2010.09.009</pub-id></citation></ref>
<ref id="B94"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Li</surname> <given-names>Z.</given-names></name> <name><surname>Zhu</surname> <given-names>H.</given-names></name> <name><surname>Xie</surname> <given-names>D.</given-names></name> <name><surname>Wang</surname> <given-names>K.</given-names></name> <name><surname>Cao</surname> <given-names>A.</given-names></name> <name><surname>Wei</surname> <given-names>J.</given-names></name> <etal/></person-group> (<year>2011b</year>). <article-title>Flame synthesis of few-layered graphene/graphite films</article-title>. <source>Chem. Commun.</source> <volume>47</volume>, <fpage>3520</fpage>&#x02013;<lpage>3522</lpage>.<pub-id pub-id-type="doi">10.1039/c0cc05139j</pub-id><pub-id pub-id-type="pmid">21308121</pub-id></citation></ref>
<ref id="B95"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Liu</surname> <given-names>F.</given-names></name> <name><surname>Ming</surname> <given-names>P.</given-names></name> <name><surname>Li</surname> <given-names>J.</given-names></name></person-group> (<year>2007</year>). <article-title>Ab initio calculation of ideal strength and phonon instability of graphene under tension</article-title>. <source>Phys. Rev. B</source> <volume>76</volume>, <fpage>064120</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.76.064120</pub-id></citation></ref>
<ref id="B96"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Loh</surname> <given-names>K. P.</given-names></name> <name><surname>Bao</surname> <given-names>Q.</given-names></name> <name><surname>Anga</surname> <given-names>P. K.</given-names></name> <name><surname>Yang</surname> <given-names>J.</given-names></name></person-group> (<year>2010</year>). <article-title>The chemistry of graphene</article-title>. <source>J. Mater. Chem.</source> <volume>20</volume>, <fpage>2277</fpage>&#x02013;<lpage>2289</lpage>.<pub-id pub-id-type="doi">10.1039/b920539j</pub-id></citation></ref>
<ref id="B97"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Loomis</surname> <given-names>J.</given-names></name> <name><surname>King</surname> <given-names>B.</given-names></name> <name><surname>Burkhead</surname> <given-names>T.</given-names></name> <name><surname>Xu</surname> <given-names>P.</given-names></name> <name><surname>Bessler</surname> <given-names>N.</given-names></name> <name><surname>Terentjev</surname> <given-names>E.</given-names></name> <etal/></person-group> (<year>2012</year>). <article-title>Graphene-nanoplatelet-based photomechanical actuators</article-title>. <source>Nanotechnology</source> <volume>23</volume>, <fpage>045501</fpage>.<pub-id pub-id-type="doi">10.1088/0957-4484/23/4/045501</pub-id><pub-id pub-id-type="pmid">22222415</pub-id></citation></ref>
<ref id="B98"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Losurdo</surname> <given-names>M.</given-names></name> <name><surname>Giangregorio</surname> <given-names>M. M.</given-names></name> <name><surname>Capezzuto</surname> <given-names>P.</given-names></name> <name><surname>Bruno</surname> <given-names>G.</given-names></name></person-group> (<year>2011</year>). <article-title>Graphene CVD growth on copper and nickel: role of hydrogen in kinetics and structure</article-title>. <source>Phys. Chem. Chem. Phys.</source> <volume>13</volume>, <fpage>20836</fpage>&#x02013;<lpage>20843</lpage>.<pub-id pub-id-type="doi">10.1039/c1cp22347j</pub-id><pub-id pub-id-type="pmid">22006173</pub-id></citation></ref>
<ref id="B99"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Lotya</surname> <given-names>M.</given-names></name> <name><surname>Hernandez</surname> <given-names>Y.</given-names></name> <name><surname>King</surname> <given-names>P. J.</given-names></name> <name><surname>Smith</surname> <given-names>R. J.</given-names></name> <name><surname>Nicolosi</surname> <given-names>V.</given-names></name> <name><surname>Karlsson</surname> <given-names>L. S.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Liquid phase production of graphene by exfoliation of graphite in surfactant/water solutions</article-title>. <source>J. Am. Chem. Soc.</source> <volume>131</volume>, <fpage>3611</fpage>&#x02013;<lpage>3620</lpage>.<pub-id pub-id-type="doi">10.1021/ja807449u</pub-id><pub-id pub-id-type="pmid">19227978</pub-id></citation></ref>
<ref id="B100"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Luechinger</surname> <given-names>N. A.</given-names></name> <name><surname>Athanassiou</surname> <given-names>E. K.</given-names></name> <name><surname>Stark</surname> <given-names>W. J.</given-names></name></person-group> (<year>2008</year>). <article-title>Graphene-stabilized copper nanoparticles as an air-stable substitute for silver and gold in low-cost ink-jet printable electronics</article-title>. <source>Nanotechnology</source> <volume>19</volume>, <fpage>445201</fpage>.<pub-id pub-id-type="doi">10.1088/0957-4484/19/44/445201</pub-id><pub-id pub-id-type="pmid">21832722</pub-id></citation></ref>
<ref id="B101"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Luk&#x02019;yanchuk</surname> <given-names>I. A.</given-names></name> <name><surname>Varlamov</surname> <given-names>A. A.</given-names></name> <name><surname>Kavokin</surname> <given-names>A. V.</given-names></name></person-group> (<year>2015</year>). <article-title>Observation of a giant two-dimensional band-piezoelectric effect on biaxial-strained graphene</article-title>. <source>NPG Asia Mater</source> <volume>7</volume>, <fpage>e154</fpage>.<pub-id pub-id-type="doi">10.1038/am.2014.124</pub-id><pub-id pub-id-type="pmid">21797559</pub-id></citation></ref>
<ref id="B102"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Malesevic</surname> <given-names>A.</given-names></name> <name><surname>Vitchev</surname> <given-names>R.</given-names></name> <name><surname>Schouteden</surname> <given-names>K.</given-names></name> <name><surname>Volodin</surname> <given-names>A.</given-names></name> <name><surname>Zhang</surname> <given-names>L.</given-names></name> <name><surname>Tendeloo</surname> <given-names>G. V.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Synthesis of few-layer graphene via microwave plasma-enhanced chemical vapour deposition</article-title>. <source>Nanotechnology</source> <volume>19</volume>, <fpage>305604</fpage>.<pub-id pub-id-type="doi">10.1088/0957-4484/19/30/305604</pub-id><pub-id pub-id-type="pmid">21828766</pub-id></citation></ref>
<ref id="B103"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Martin</surname> <given-names>J. A.</given-names></name> <name><surname>Vazquez</surname> <given-names>L.</given-names></name> <name><surname>Bernard</surname> <given-names>P.</given-names></name> <name><surname>Comin</surname> <given-names>F.</given-names></name> <name><surname>Ferrer</surname> <given-names>S.</given-names></name></person-group> (<year>1990</year>). <article-title>Epitaxial growth of crystalline, diamond-like films on Si(100) by laser ablation of graphite</article-title>. <source>Appl. Phys. Lett.</source> <volume>57</volume>, <fpage>1742</fpage>&#x02013;<lpage>1744</lpage>.<pub-id pub-id-type="doi">10.1063/1.104053</pub-id></citation></ref>
<ref id="B104"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mattevi</surname> <given-names>C.</given-names></name> <name><surname>Kima</surname> <given-names>H.</given-names></name> <name><surname>Chhowalla</surname> <given-names>M.</given-names></name></person-group> (<year>2011</year>). <article-title>A review of chemical vapour deposition of graphene on copper</article-title>. <source>J. Mater. Chem.</source> <volume>21</volume>, <fpage>3324</fpage>&#x02013;<lpage>3334</lpage>.<pub-id pub-id-type="doi">10.1039/C0JM02126A</pub-id></citation></ref>
<ref id="B105"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mayorov</surname> <given-names>A. S.</given-names></name> <name><surname>Gorbachev</surname> <given-names>R. V.</given-names></name> <name><surname>Morozov</surname> <given-names>S. V.</given-names></name> <name><surname>Britnell</surname> <given-names>L.</given-names></name> <name><surname>Jalil</surname> <given-names>R.</given-names></name> <name><surname>Ponomarenko</surname> <given-names>L. A.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Micrometer-scale ballistic transport in encapsulated graphene at room temperature</article-title>. <source>Nano Lett.</source> <volume>11</volume>, <fpage>2396</fpage>&#x02013;<lpage>2399</lpage>.<pub-id pub-id-type="doi">10.1021/nl200758b</pub-id><pub-id pub-id-type="pmid">21574627</pub-id></citation></ref>
<ref id="B106"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mazzamuto</surname> <given-names>F.</given-names></name> <name><surname>Hung Nguyen</surname> <given-names>V.</given-names></name> <name><surname>Apertet</surname> <given-names>Y.</given-names></name> <name><surname>Ca</surname> <given-names>C.</given-names></name> <name><surname>Chassat</surname> <given-names>C.</given-names></name> <name><surname>Saint-Martin</surname> <given-names>J.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Enhanced thermoelectric properties in graphene nanoribbons by resonant tunneling of electrons</article-title>. <source>Phys. Rev. B</source> <volume>83</volume>, <fpage>235426</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.83.235426</pub-id></citation></ref>
<ref id="B107"><citation citation-type="web"><person-group person-group-type="author"><name><surname>Meador</surname> <given-names>M. A.</given-names></name> <etal/></person-group> (<year>2010</year>). <source>DRAFT Nanotechnology Roadmap Technology Area 10. National Aeronautics and Space Administration (NASA)</source>. <fpage>5</fpage>. Available at: <uri xlink:href="http://www.nasa.gov/pdf/501325main_TA10-Nanotech-DRAFT-Nov2010-A.pdf">http://www.nasa.gov/pdf/501325main_TA10-Nanotech-DRAFT-Nov2010-A.pdf</uri></citation></ref>
<ref id="B108"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Memon</surname> <given-names>N. K.</given-names></name> <name><surname>Tse</surname> <given-names>S. D.</given-names></name> <name><surname>Al-Sharab</surname> <given-names>J. F.</given-names></name> <name><surname>Yamaguchi</surname> <given-names>H.</given-names></name> <name><surname>Goncalves</surname> <given-names>A.-M. B.</given-names></name> <name><surname>Kear</surname> <given-names>B. H.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Flame synthesis of graphene films in open environments</article-title>. <source>Carbon N. Y.</source> <volume>49</volume>, <fpage>5064</fpage>&#x02013;<lpage>5070</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2011.07.024</pub-id></citation></ref>
<ref id="B109"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Memon</surname> <given-names>N. K.</given-names></name> <name><surname>Anjum</surname> <given-names>D. H.</given-names></name> <name><surname>Chung</surname> <given-names>S. H.</given-names></name></person-group> (<year>2013</year>). <article-title>Multiple-diffusion flame synthesis of pure anatase and carbon-coated titanium dioxide nanoparticles</article-title>. <source>Combust. Flame</source> <volume>160</volume>, <fpage>1848</fpage>&#x02013;<lpage>1856</lpage>.<pub-id pub-id-type="doi">10.1016/j.combustflame.2013.03.022</pub-id></citation></ref>
<ref id="B110"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Morozov</surname> <given-names>S. V.</given-names></name> <name><surname>Novoselov</surname> <given-names>K. S.</given-names></name> <name><surname>Katsnelson</surname> <given-names>M. I.</given-names></name> <name><surname>Schedin</surname> <given-names>F.</given-names></name> <name><surname>Elias</surname> <given-names>D. C.</given-names></name> <name><surname>Jaszczak</surname> <given-names>J. A.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Giant intrinsic carrier mobilities in graphene and its bilayer</article-title>. <source>Phys. Rev. Lett.</source> <volume>100</volume>, <fpage>016602</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.100.016602</pub-id><pub-id pub-id-type="pmid">18232798</pub-id></citation></ref>
<ref id="B111"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Moser</surname> <given-names>J.</given-names></name> <name><surname>Barreiro</surname> <given-names>A.</given-names></name> <name><surname>Bachtold</surname> <given-names>A.</given-names></name></person-group> (<year>2007</year>). <article-title>Current-induced cleaning of graphene</article-title>. <source>Appl. Phys. Lett.</source> <volume>91</volume>, <fpage>163513</fpage>.<pub-id pub-id-type="doi">10.1063/1.2789673</pub-id></citation></ref>
<ref id="B112"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Muge</surname> <given-names>A.</given-names></name> <name><surname>Chabal</surname> <given-names>Y. J.</given-names></name></person-group> (<year>2011</year>). <article-title>Nature of graphene edges: a review</article-title>. <source>Jpn. J. Appl. Phys.</source> <volume>50</volume>, <fpage>070101</fpage>.<pub-id pub-id-type="doi">10.1021/ar500306w</pub-id><pub-id pub-id-type="pmid">25539031</pub-id></citation></ref>
<ref id="B113"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nair</surname> <given-names>R. R.</given-names></name> <name><surname>Blake</surname> <given-names>P.</given-names></name> <name><surname>Grigorenko</surname> <given-names>A. N.</given-names></name> <name><surname>Novoselov</surname> <given-names>K. S.</given-names></name> <name><surname>Booth</surname> <given-names>T. J.</given-names></name> <name><surname>Stauber</surname> <given-names>T.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Fine structure constant defines visual transparency of graphene</article-title>. <source>Science</source> <volume>320</volume>, <fpage>1308</fpage>.<pub-id pub-id-type="doi">10.1126/science.1156965</pub-id><pub-id pub-id-type="pmid">18388259</pub-id></citation></ref>
<ref id="B114"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nair</surname> <given-names>R. R.</given-names></name> <name><surname>Ren</surname> <given-names>W.</given-names></name> <name><surname>Jalil</surname> <given-names>R.</given-names></name> <name><surname>Riaz</surname> <given-names>I.</given-names></name> <name><surname>Kravets</surname> <given-names>V. G.</given-names></name> <name><surname>Britnell</surname> <given-names>L.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Fluorographene: a two-dimensional counterpart of teflon</article-title>. <source>Small</source> <volume>6</volume>, <fpage>2877</fpage>&#x02013;<lpage>2884</lpage>.<pub-id pub-id-type="doi">10.1002/smll.201001555</pub-id><pub-id pub-id-type="pmid">21053339</pub-id></citation></ref>
<ref id="B115"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nakamura</surname> <given-names>K.</given-names></name> <name><surname>Fukazawa</surname> <given-names>K.</given-names></name> <name><surname>Yamada</surname> <given-names>K.</given-names></name> <name><surname>Saito</surname> <given-names>S.</given-names></name></person-group> (<year>1989</year>). <article-title>Hysteresis-free piezoelectric actuators using linbo3 plates with a ferroelectric inversion layer</article-title>. <source>Ferroelectrics</source> <volume>93</volume>, <fpage>211</fpage>&#x02013;<lpage>216</lpage>.<pub-id pub-id-type="doi">10.1080/00150198908017348</pub-id><pub-id pub-id-type="pmid">14682639</pub-id></citation></ref>
<ref id="B116"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nechache</surname> <given-names>R.</given-names></name> <name><surname>Harnagea</surname> <given-names>C.</given-names></name> <name><surname>Pignolet</surname> <given-names>A.</given-names></name> <name><surname>Normandin</surname> <given-names>F.</given-names></name> <name><surname>Veres</surname> <given-names>T.</given-names></name> <name><surname>Carignan</surname> <given-names>L.-Ph.</given-names></name> <etal/></person-group> (<year>2006</year>). <article-title>Growth, structure, and properties of epitaxial thin films of first-principles predicted multiferroic Bi2FeCrO6</article-title>. <source>Appl. Phys. Lett.</source> <volume>89</volume>, <fpage>102902</fpage>&#x02013;<lpage>102902&#x02013;3</lpage>.<pub-id pub-id-type="doi">10.1063/1.2346258</pub-id></citation></ref>
<ref id="B117"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Neto</surname> <given-names>A. H. C.</given-names></name> <name><surname>Guinea</surname> <given-names>F.</given-names></name> <name><surname>Peres</surname> <given-names>N. M. R.</given-names></name> <name><surname>Novoselov</surname> <given-names>K. S.</given-names></name> <name><surname>Geim</surname> <given-names>A. K.</given-names></name></person-group> (<year>2009</year>). <article-title>The electronic properties of graphene</article-title>. <source>Rev. Mod. Phys.</source> <volume>81</volume>, <fpage>109</fpage>&#x02013;<lpage>162</lpage>.<pub-id pub-id-type="doi">10.1103/RevModPhys.81.109</pub-id></citation></ref>
<ref id="B118"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ni</surname> <given-names>Z.</given-names></name> <name><surname>Wang</surname> <given-names>Y.</given-names></name> <name><surname>Yu</surname> <given-names>T.</given-names></name> <name><surname>Shen</surname> <given-names>Z.</given-names></name></person-group> (<year>2008</year>). <article-title>Raman spectroscopy and imaging of graphene</article-title>. <source>Nano Res.</source> <volume>1</volume>, <fpage>273</fpage>&#x02013;<lpage>291</lpage>.<pub-id pub-id-type="doi">10.1007/s12274-008-8036-1</pub-id></citation></ref>
<ref id="B119"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Novoselov</surname> <given-names>K. S.</given-names></name> <name><surname>Geim</surname> <given-names>A. K.</given-names></name> <name><surname>Morozov</surname> <given-names>S. V.</given-names></name> <name><surname>Jiang</surname> <given-names>D.</given-names></name> <name><surname>Katsnelson</surname> <given-names>M. I.</given-names></name> <name><surname>Grigorieva</surname> <given-names>I. V.</given-names></name> <etal/></person-group> (<year>2005</year>). <article-title>Two-dimensional gas of massless dirac fermions in graphene</article-title>. <source>Nature</source> <volume>438</volume>, <fpage>197</fpage>&#x02013;<lpage>200</lpage>.<pub-id pub-id-type="doi">10.1038/nature04233</pub-id><pub-id pub-id-type="pmid">16281030</pub-id></citation></ref>
<ref id="B120"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Novoselov</surname> <given-names>K. S.</given-names></name> <name><surname>Geim</surname> <given-names>A. K.</given-names></name> <name><surname>Morozov</surname> <given-names>S. V.</given-names></name> <name><surname>Jiang</surname> <given-names>D.</given-names></name> <name><surname>Zhang</surname> <given-names>Y.</given-names></name> <name><surname>Dubonos</surname> <given-names>S. V.</given-names></name> <etal/></person-group> (<year>2004</year>). <article-title>Electric field effect in atomically thin carbon films</article-title>. <source>Science</source> <volume>306</volume>, <fpage>666</fpage>&#x02013;<lpage>669</lpage>.<pub-id pub-id-type="doi">10.1126/science.1102896</pub-id><pub-id pub-id-type="pmid">15499015</pub-id></citation></ref>
<ref id="B121"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ohta</surname> <given-names>H.</given-names></name> <name><surname>Kim</surname> <given-names>S.</given-names></name> <name><surname>Mune</surname> <given-names>Y.</given-names></name> <name><surname>Mizoguchi</surname> <given-names>T.</given-names></name> <name><surname>Nomura</surname> <given-names>K.</given-names></name> <name><surname>Ohta</surname> <given-names>S.</given-names></name> <etal/></person-group> (<year>2007</year>). <article-title>Giant thermoelectric Seebeck coefficient of a two-dimensional electron gas in SrTiO3</article-title>. <source>Nat. Mater.</source> <volume>6</volume>, <fpage>129</fpage>&#x02013;<lpage>134</lpage>.<pub-id pub-id-type="doi">10.1038/nmat1821</pub-id><pub-id pub-id-type="pmid">17237790</pub-id></citation></ref>
<ref id="B122"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ossler</surname> <given-names>F.</given-names></name> <name><surname>Wagner</surname> <given-names>J.</given-names></name> <name><surname>Canton</surname> <given-names>S.</given-names></name> <name><surname>Wallenberg</surname> <given-names>R.</given-names></name></person-group> (<year>2010</year>). <article-title>Sheet-like carbon particles with graphene structures obtained from a Bunsen flame</article-title>. <source>Carbon N. Y.</source> <volume>48</volume>, <fpage>4203</fpage>&#x02013;<lpage>4206</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2010.07.013</pub-id></citation></ref>
<ref id="B123"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ouyang</surname> <given-names>F.</given-names></name> <name><surname>Peng</surname> <given-names>S.</given-names></name> <name><surname>Liu</surname> <given-names>Z.</given-names></name> <name><surname>Liu</surname> <given-names>Z.</given-names></name></person-group> (<year>2011</year>). <article-title>Bandgap opening in graphene antidot lattices: the missing half</article-title>. <source>ACS Nano</source> <volume>5</volume>, <fpage>4023</fpage>&#x02013;<lpage>4030</lpage>.<pub-id pub-id-type="doi">10.1021/nn200580w</pub-id><pub-id pub-id-type="pmid">21513306</pub-id></citation></ref>
<ref id="B124"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ouyang</surname> <given-names>T.</given-names></name> <name><surname>Hu</surname> <given-names>M.</given-names></name></person-group> (<year>2010</year>). <article-title>Enhanced thermoelectric figure of merit in edge-disordered zigzag graphene nanoribbons</article-title>. <source>Phys. Rev. B</source> <volume>81</volume>, <fpage>113401</fpage>.<pub-id pub-id-type="doi">10.1088/0957-4484/25/24/245401</pub-id><pub-id pub-id-type="pmid">24859889</pub-id></citation></ref>
<ref id="B125"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Park</surname> <given-names>J.</given-names></name> <name><surname>Kim</surname> <given-names>B.K.</given-names></name></person-group> (<year>2014</year>). <article-title>Infrared light actuated shape memory effects in crystalline polyurethane/graphene chemical hybrids</article-title>. <source>Smart Mater. Struct.</source> <volume>23</volume>, <fpage>025038</fpage>.<pub-id pub-id-type="doi">10.1088/0964-1726/23/2/025038</pub-id></citation></ref>
<ref id="B126"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Park</surname> <given-names>J. B.</given-names></name> <name><surname>Xiong</surname> <given-names>W.</given-names></name> <name><surname>Gao</surname> <given-names>Y.</given-names></name> <name><surname>Qian</surname> <given-names>M.</given-names></name> <name><surname>Xie</surname> <given-names>Z. Q.</given-names></name> <name><surname>Mitchell</surname> <given-names>M.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Fast growth of graphene patterns by laser direct writing</article-title>. <source>Appl. Phys. Lett.</source> <volume>98</volume>, <fpage>123109</fpage>.<pub-id pub-id-type="doi">10.1063/1.3569720</pub-id></citation></ref>
<ref id="B127"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Pedersen</surname> <given-names>T. G.</given-names></name> <name><surname>Flindt</surname> <given-names>C.</given-names></name> <name><surname>Pedersen</surname> <given-names>J.</given-names></name> <name><surname>Mortensen</surname> <given-names>N. A.</given-names></name> <name><surname>Jauho</surname> <given-names>A. P.</given-names></name> <name><surname>Pedersen</surname> <given-names>K.</given-names></name></person-group> (<year>2008</year>). <article-title>Graphene antidot lattices: designed defects and spin qubits</article-title>. <source>Phys. Rev. Lett.</source> <volume>100</volume>, <fpage>136804</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.100.136804</pub-id><pub-id pub-id-type="pmid">18517984</pub-id></citation></ref>
<ref id="B128"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Pereira</surname> <given-names>V. M.</given-names></name> <name><surname>Castro Neto</surname> <given-names>A. H.</given-names></name></person-group> (<year>2009</year>). <article-title>Strain engineering of graphene&#x02019;s electronic structure</article-title>. <source>Phys. Rev. Lett.</source> <volume>103</volume>, <fpage>046801</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.103.046801</pub-id><pub-id pub-id-type="pmid">19659379</pub-id></citation></ref>
<ref id="B129"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Petersen</surname> <given-names>R.</given-names></name> <name><surname>Pedersen</surname> <given-names>T. G.</given-names></name> <name><surname>Jauho</surname> <given-names>A. P.</given-names></name></person-group> (<year>2011</year>). <article-title>Clar sextet analysis of triangular, rectangular, and honeycomb graphene antidot lattices</article-title>. <source>ACS Nano</source> <volume>5</volume>, <fpage>523</fpage>&#x02013;<lpage>529</lpage>.<pub-id pub-id-type="doi">10.1021/nn102442h</pub-id><pub-id pub-id-type="pmid">21158482</pub-id></citation></ref>
<ref id="B130"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ponnamma</surname> <given-names>D.</given-names></name> <name><surname>Guo</surname> <given-names>Q.</given-names></name> <name><surname>Krupa</surname> <given-names>I.</given-names></name> <name><surname>Al-Maadeed</surname> <given-names>M. A.</given-names></name> <name><surname>K</surname> <given-names>T. V.</given-names></name> <name><surname>Thomas</surname> <given-names>S.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Recent advances in graphene based polymer composites</article-title>. <source>Prog. Polym. Sci.</source> <volume>35</volume>, <fpage>1350</fpage>&#x02013;<lpage>1375</lpage>.<pub-id pub-id-type="doi">10.1039/c4cp04418e</pub-id><pub-id pub-id-type="pmid">25585199</pub-id></citation></ref>
<ref id="B131"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Potts</surname> <given-names>J. R.</given-names></name> <name><surname>Dreyer</surname> <given-names>D. R.</given-names></name> <name><surname>Bielawski</surname> <given-names>C. W.</given-names></name> <name><surname>Ruoff</surname> <given-names>R. S.</given-names></name></person-group> (<year>2011</year>). <article-title>Graphene-based polymer nanocomposites</article-title>. <source>Polymer</source> <volume>52</volume>, <fpage>5</fpage>&#x02013;<lpage>25</lpage>.<pub-id pub-id-type="doi">10.1016/j.polymer.2010.11.042</pub-id></citation></ref>
<ref id="B132"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Rana</surname> <given-names>S.</given-names></name> <name><surname>Cho</surname> <given-names>J. W.</given-names></name> <name><surname>Tan</surname> <given-names>L. P.</given-names></name></person-group> (<year>2013</year>). <article-title>Graphene-crosslinked polyurethane block copolymer nanocomposites with enhanced mechanical, electrical, and shape memory properties</article-title>. <source>RSC Adv.</source> <volume>3</volume>, <fpage>13796</fpage>&#x02013;<lpage>13803</lpage>.<pub-id pub-id-type="doi">10.1039/c3ra40711j</pub-id></citation></ref>
<ref id="B133"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Reina</surname> <given-names>A.</given-names></name> <name><surname>Jia</surname> <given-names>X.</given-names></name> <name><surname>Ho</surname> <given-names>J.</given-names></name> <name><surname>Nezich</surname> <given-names>D.</given-names></name> <name><surname>Son</surname> <given-names>H.</given-names></name> <name><surname>Bulovic</surname> <given-names>V.</given-names></name> <etal/></person-group> (<year>2008</year>). <article-title>Large area, few-layer graphene films on arbitrary substrates by chemical vapor deposition</article-title>. <source>Nano Lett.</source> <volume>9</volume>, <fpage>30</fpage>&#x02013;<lpage>35</lpage>.<pub-id pub-id-type="doi">10.1021/nl801827v</pub-id></citation></ref>
<ref id="B134"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Reina</surname> <given-names>A.</given-names></name> <name><surname>Jia</surname> <given-names>X.</given-names></name> <name><surname>Ho</surname> <given-names>J.</given-names></name> <name><surname>Nezich</surname> <given-names>D.</given-names></name> <name><surname>Son</surname> <given-names>H.</given-names></name> <name><surname>Bulovic</surname> <given-names>V.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Large area, few-layer graphene films on arbitrary substrates by chemical vapor deposition</article-title>. <source>Nano Lett.</source> <volume>9</volume>, <fpage>30</fpage>&#x02013;<lpage>35</lpage>.<pub-id pub-id-type="doi">10.1021/nl801827v</pub-id><pub-id pub-id-type="pmid">19046078</pub-id></citation></ref>
<ref id="B135"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ren</surname> <given-names>Z. F.</given-names></name> <name><surname>Huang</surname> <given-names>Z. P.</given-names></name> <name><surname>Xu</surname> <given-names>J. W.</given-names></name> <name><surname>Wang</surname> <given-names>J. H.</given-names></name> <name><surname>Bush</surname> <given-names>P.</given-names></name> <name><surname>Siegal</surname> <given-names>M. P.</given-names></name> <etal/></person-group> (<year>1998</year>). <article-title>Synthesis of large arrays of well-aligned carbon nanotubes on glass</article-title>. <source>Science</source> <volume>282</volume>, <fpage>1105</fpage>&#x02013;<lpage>1107</lpage>.<pub-id pub-id-type="doi">10.1126/science.282.5391.1105</pub-id><pub-id pub-id-type="pmid">9804545</pub-id></citation></ref>
<ref id="B136"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Saravanakumar</surname> <given-names>B.</given-names></name> <name><surname>Mohan</surname> <given-names>R.</given-names></name> <name><surname>Kim</surname> <given-names>S.-J.</given-names></name></person-group> (<year>2013</year>). <article-title>Facile synthesis of graphene/ZnO nanocomposites by low temperature hydrothermal method</article-title>. <source>Mater. Res. Bull.</source> <volume>48</volume>, <fpage>878</fpage>&#x02013;<lpage>883</lpage>.<pub-id pub-id-type="doi">10.1016/j.materresbull.2012.11.048</pub-id></citation></ref>
<ref id="B137"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sarma</surname> <given-names>S. D.</given-names></name> <name><surname>Adam</surname> <given-names>S.</given-names></name> <name><surname>Hwang</surname> <given-names>E. H.</given-names></name> <name><surname>Rossi</surname> <given-names>E.</given-names></name></person-group> (<year>2011</year>). <article-title>Electronic transport in two-dimensional graphene</article-title>. <source>Rev. Mod. Phys.</source> <volume>83</volume>, <fpage>407</fpage>&#x02013;<lpage>470</lpage>.<pub-id pub-id-type="doi">10.1103/RevModPhys.83.407</pub-id></citation></ref>
<ref id="B138"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Schwierz</surname> <given-names>F.</given-names></name></person-group> (<year>2010</year>). <article-title>Graphene transistors</article-title>. <source>Nat. Nanotechnol.</source> <volume>5</volume>, <fpage>487</fpage>&#x02013;<lpage>496</lpage>.<pub-id pub-id-type="doi">10.1038/nnano.2010.89</pub-id></citation></ref>
<ref id="B139"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sevin&#x000E7;li</surname> <given-names>H.</given-names></name> <name><surname>Sevik</surname> <given-names>C.</given-names></name> <name><surname>Ca&#x00131;n</surname> <given-names>T.</given-names></name> <name><surname>Cuniberti</surname> <given-names>G.</given-names></name></person-group> (<year>2009</year>). <article-title>Disorder enhances thermoelectric figure of merit in armchair graphane nanoribbons</article-title>. <source>Appl. Phys. Lett.</source> <volume>95</volume>, <fpage>192114</fpage>.<pub-id pub-id-type="doi">10.1038/srep01228</pub-id><pub-id pub-id-type="pmid">23390578</pub-id></citation></ref>
<ref id="B140"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sharma</surname> <given-names>R.</given-names></name> <name><surname>Alam</surname> <given-names>F.</given-names></name> <name><surname>Sharma</surname> <given-names>A. K.</given-names></name> <name><surname>Dutta</surname> <given-names>V.</given-names></name> <name><surname>Dhawan</surname> <given-names>S. K.</given-names></name></person-group> (<year>2014</year>). <article-title>ZnO anchored graphene hydrophobic nanocomposite-based bulk heterojunction solar cells showing enhanced short-circuit current</article-title>. <source>J. Mater. Chem. C</source> <volume>2</volume>, <fpage>8142</fpage>&#x02013;<lpage>8151</lpage>.<pub-id pub-id-type="doi">10.1039/C4TC01056F</pub-id></citation></ref>
<ref id="B141"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Shen</surname> <given-names>T.</given-names></name> <name><surname>Wu</surname> <given-names>Y. Q.</given-names></name> <name><surname>Capano</surname> <given-names>M. A.</given-names></name> <name><surname>Rokhinson</surname> <given-names>L. P.</given-names></name> <name><surname>Engel</surname> <given-names>L. W.</given-names></name> <name><surname>Ye</surname> <given-names>P. D.</given-names></name></person-group> (<year>2008</year>). <article-title>Magneto-conductance oscillations in graphene antidot arrays</article-title>. <source>Appl. Phys. Lett.</source> <volume>93</volume>, <fpage>122102</fpage>.<pub-id pub-id-type="doi">10.1063/1.2988725</pub-id></citation></ref>
<ref id="B70"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Shinde</surname> <given-names>S. R.</given-names></name> <name><surname>Ogale</surname> <given-names>S. B.</given-names></name> <name><surname>Greene</surname> <given-names>R. L.</given-names></name> <name><surname>Venkatesan</surname> <given-names>T.</given-names></name> <name><surname>Canfield</surname> <given-names>P. C.</given-names></name> <name><surname>Bud&#x02019;ko</surname> <given-names>S. L.</given-names></name> <etal/></person-group> (<year>2001</year>). <article-title>Superconducting MgB2 thin films by pulsed laser deposition</article-title>. <source>Appl. Phys. Lett.</source> <volume>79</volume>, <fpage>227</fpage>&#x02013;<lpage>229</lpage>.<pub-id pub-id-type="doi">10.1063/1.1385186</pub-id><pub-id pub-id-type="pmid">11303089</pub-id></citation></ref>
<ref id="B142"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Shim</surname> <given-names>J.-P.</given-names></name> <name><surname>Choe</surname> <given-names>M.</given-names></name> <name><surname>Jeon</surname> <given-names>S.-R.</given-names></name> <name><surname>Seo</surname> <given-names>D.</given-names></name> <name><surname>Lee</surname> <given-names>T.</given-names></name> <name><surname>Lee</surname> <given-names>D.-S.</given-names></name></person-group>, (<year>2011</year>). <article-title>InGaN-based p&#x02013;i&#x02013;n solar cells with graphene electrodes</article-title>. <source>Appl. Phys. Express</source> <volume>4</volume>, <fpage>052302</fpage>.<pub-id pub-id-type="doi">10.1143/APEX.4.052302</pub-id></citation></ref>
<ref id="B143"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Singh</surname> <given-names>V.</given-names></name> <name><surname>Joung</surname> <given-names>D.</given-names></name> <name><surname>Zhai</surname> <given-names>L.</given-names></name> <name><surname>Das</surname> <given-names>S.</given-names></name> <name><surname>Khondaker</surname> <given-names>S. I.</given-names></name> <name><surname>Seal</surname> <given-names>S.</given-names></name></person-group> (<year>2011</year>). <article-title>Graphene based materials: past, present and future</article-title>. <source>Prog. Mater. Sci.</source> <volume>56</volume>, <fpage>1178</fpage>&#x02013;<lpage>1271</lpage>.<pub-id pub-id-type="doi">10.1016/j.pmatsci.2011.03.003</pub-id></citation></ref>
<ref id="B144"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Smela</surname> <given-names>E.</given-names></name> <name><surname>Gadegaard</surname> <given-names>N.</given-names></name></person-group> (<year>1999</year>). <article-title>Surprising volume change in PPy(DBS): an atomic force microscopy study</article-title>. <source>Adv. Mater.</source> <volume>11</volume>, <fpage>953</fpage>.<pub-id pub-id-type="doi">10.1002/(SICI)1521-4095(199908)11:11&#x0003C;953::AID-ADMA953&#x0003E;3.3.CO;2-8</pub-id></citation></ref>
<ref id="B145"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Smith</surname> <given-names>H.M.</given-names></name> <name><surname>Turner</surname> <given-names>A.F.</given-names></name></person-group> (<year>1965</year>). <article-title>Vacuum deposited thin films using a ruby laser</article-title>. <source>Appl. Opt.</source> <volume>4</volume>, <fpage>147</fpage>&#x02013;<lpage>148</lpage>.<pub-id pub-id-type="doi">10.1364/AO.4.000147</pub-id></citation></ref>
<ref id="B146"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Stankovich</surname> <given-names>S.</given-names></name> <name><surname>Dikin</surname> <given-names>D. A.</given-names></name> <name><surname>Dommett</surname> <given-names>G. H.</given-names></name> <name><surname>Kohlhaas</surname> <given-names>K. M.</given-names></name> <name><surname>Zimney</surname> <given-names>E. J.</given-names></name> <name><surname>Stach</surname> <given-names>E. A.</given-names></name> <etal/></person-group> (<year>2006</year>). <article-title>Graphene-based composite materials</article-title>. <source>Nature</source> <volume>442</volume>, <fpage>282</fpage>&#x02013;<lpage>286</lpage>.<pub-id pub-id-type="doi">10.1038/nature04969</pub-id><pub-id pub-id-type="pmid">16855586</pub-id></citation></ref>
<ref id="B147"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Suemitsu</surname> <given-names>M.</given-names></name> <name><surname>Fukidome</surname> <given-names>H.</given-names></name></person-group> (<year>2010</year>). <article-title>Epitaxial graphene on silicon substrates</article-title>. <source>J. Phys. D Appl. Phys.</source> <volume>43</volume>, <fpage>374012</fpage>.<pub-id pub-id-type="doi">10.1088/0022-3727/43/37/374012</pub-id></citation></ref>
<ref id="B148"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Suk</surname> <given-names>J. W.</given-names></name> <name><surname>Kitt</surname> <given-names>A.</given-names></name> <name><surname>Magnuson</surname> <given-names>C. W.</given-names></name> <name><surname>Hao</surname> <given-names>Y.</given-names></name> <name><surname>Ahmed</surname> <given-names>S.</given-names></name> <name><surname>An</surname> <given-names>J.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Transfer of CVD-grown monolayer graphene onto arbitrary substrates</article-title>. <source>ACS Nano</source> <volume>5</volume>, <fpage>6916</fpage>&#x02013;<lpage>6924</lpage>.<pub-id pub-id-type="doi">10.1021/nn201207c</pub-id><pub-id pub-id-type="pmid">21894965</pub-id></citation></ref>
<ref id="B149"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sullivan</surname> <given-names>T. D.</given-names></name> <name><surname>Powers</surname> <given-names>J. M.</given-names></name></person-group> (<year>1977</year>). <article-title>Flexural disc piezoelectric polymer hydrophones</article-title>. <source>J. Acoust. Soc. Am.</source> <volume>60</volume>, <fpage>S47</fpage>&#x02013;<lpage>S47</lpage>.</citation></ref>
<ref id="B150"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sun</surname> <given-names>Z.</given-names></name> <name><surname>Hasan</surname> <given-names>T.</given-names></name> <name><surname>Torrisi</surname> <given-names>F.</given-names></name> <name><surname>Popa</surname> <given-names>D.</given-names></name> <name><surname>Privitera</surname> <given-names>G.</given-names></name> <name><surname>Wang</surname> <given-names>F.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Graphene mode-locked ultrafast laser</article-title>. <source>ACS Nano</source> <volume>4</volume>, <fpage>803</fpage>.<pub-id pub-id-type="doi">10.1021/nn901703e</pub-id></citation></ref>
<ref id="B151"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sun</surname> <given-names>Z.</given-names></name> <name><surname>Yan</surname> <given-names>Z.</given-names></name> <name><surname>Yao</surname> <given-names>J.</given-names></name> <name><surname>Beitler</surname> <given-names>E.</given-names></name> <name><surname>Zhu</surname> <given-names>Y.</given-names></name> <name><surname>Tour</surname> <given-names>J. M.</given-names></name></person-group> (<year>2010</year>). <article-title>Growth of graphene from solid carbon sources</article-title>. <source>Nature</source> <volume>468</volume>, <fpage>549</fpage>&#x02013;<lpage>552</lpage>.<pub-id pub-id-type="doi">10.1038/nature09579</pub-id><pub-id pub-id-type="pmid">21068724</pub-id></citation></ref>
<ref id="B152"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tang</surname> <given-names>S.</given-names></name> <name><surname>Cao</surname> <given-names>Z.</given-names></name></person-group> (<year>2010</year>). <article-title>Structural and electronic properties of the fully hydrogenated boron nitride sheets and nanoribbons: insight from first-principles calculations</article-title>. <source>Chem. Phys. Lett.</source> <volume>488</volume>, <fpage>67</fpage>&#x02013;<lpage>72</lpage>.<pub-id pub-id-type="doi">10.1016/j.cplett.2010.01.073</pub-id></citation></ref>
<ref id="B153"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Thakur</surname> <given-names>S.</given-names></name> <name><surname>Karak</surname> <given-names>N.</given-names></name></person-group> (<year>2013</year>). <article-title>Bio-based tough hyperbranched polyurethane&#x02013;graphene oxide nanocomposites as advanced shape memory materials</article-title>. <source>RSC Adv.</source> <volume>3</volume>, <fpage>9476</fpage>&#x02013;<lpage>9482</lpage>.<pub-id pub-id-type="doi">10.1039/c3ra40801a</pub-id></citation></ref>
<ref id="B154"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tung</surname> <given-names>V. C.</given-names></name> <name><surname>Chen</surname> <given-names>L. M.</given-names></name> <name><surname>Allen</surname> <given-names>M. J.</given-names></name> <name><surname>Wassei</surname> <given-names>J. K.</given-names></name> <name><surname>Nelson</surname> <given-names>K.</given-names></name> <name><surname>Kaner</surname> <given-names>R. B.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Low-temperature solution processing of graphene&#x02212; carbon nanotube hybrid materials for high-performance transparent conductors</article-title>. <source>Nano Lett.</source> <volume>9</volume>, <fpage>1949</fpage>&#x02013;<lpage>1955</lpage>.<pub-id pub-id-type="doi">10.1021/nl9001525</pub-id><pub-id pub-id-type="pmid">19361207</pub-id></citation></ref>
<ref id="B155"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tyler</surname> <given-names>W.W.</given-names></name> <name><surname>Wilson</surname> <given-names>A.C.</given-names></name></person-group> (<year>1953</year>). <article-title>Thermal conductivity, electrical resistivity, and thermoelectric power of graphite</article-title>. <source>Phys. Rev.</source> <volume>89</volume>, <fpage>870</fpage>&#x02013;<lpage>875</lpage>.<pub-id pub-id-type="doi">10.1103/PhysRev.89.870</pub-id></citation></ref>
<ref id="B157"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Voon</surname> <given-names>L. C.</given-names></name> <name><surname>Sandberg</surname> <given-names>E.</given-names></name> <name><surname>Aga</surname> <given-names>R. S.</given-names></name> <name><surname>Farajian</surname> <given-names>A. A.</given-names></name></person-group> (<year>2010</year>). <article-title>Hydrogen compounds of group-IV nanosheets</article-title>. <source>Appl. Phys. Lett.</source> <volume>97</volume>, <fpage>163114</fpage>.<pub-id pub-id-type="doi">10.1063/1.3495786</pub-id></citation></ref>
<ref id="B158"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wager</surname> <given-names>J.F.</given-names></name></person-group> (<year>2003</year>). <article-title>Transparent electronics</article-title>. <source>Science</source> <volume>300</volume>, <fpage>1245</fpage>&#x02013;<lpage>1246</lpage>.<pub-id pub-id-type="doi">10.1126/science.1085276</pub-id></citation></ref>
<ref id="B159"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wan</surname> <given-names>X.</given-names></name> <name><surname>Long</surname> <given-names>G.</given-names></name> <name><surname>Huang</surname> <given-names>L.</given-names></name> <name><surname>Chen</surname> <given-names>Y.</given-names></name></person-group> (<year>2011</year>). <article-title>Graphene &#x02013; a promising material for organic photovoltaic cells</article-title>. <source>Adv. Mater. Weinheim</source> <volume>23</volume>, <fpage>5342</fpage>&#x02013;<lpage>5358</lpage>.<pub-id pub-id-type="doi">10.1002/adma.201102735</pub-id><pub-id pub-id-type="pmid">21956482</pub-id></citation></ref>
<ref id="B160"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wang</surname> <given-names>C.</given-names></name> <name><surname>Liu</surname> <given-names>N.</given-names></name> <name><surname>Allen</surname> <given-names>R.</given-names></name> <name><surname>Tok</surname> <given-names>J. B.</given-names></name> <name><surname>Wu</surname> <given-names>Y.</given-names></name> <name><surname>Zhang</surname> <given-names>F.</given-names></name> <etal/></person-group> (<year>2013</year>). <article-title>A rapid and efficient self-healing thermo-reversible elastomer crosslinked with graphene oxide</article-title>. <source>Adv. Mater. Weinheim</source> <volume>25</volume>, <fpage>5785</fpage>&#x02013;<lpage>5790</lpage>.<pub-id pub-id-type="doi">10.1002/adma.201302962</pub-id><pub-id pub-id-type="pmid">23946261</pub-id></citation></ref>
<ref id="B161"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wang</surname> <given-names>J.</given-names></name> <name><surname>Zhu</surname> <given-names>M.</given-names></name> <name><surname>Outlaw</surname> <given-names>R. A.</given-names></name> <name><surname>Zhao</surname> <given-names>X.</given-names></name> <name><surname>Manos</surname> <given-names>D. M.</given-names></name> <name><surname>Holloway</surname> <given-names>B. C.</given-names></name></person-group> (<year>2004</year>). <article-title>Synthesis of carbon nanosheets by inductively coupled radio-frequency plasma enhanced chemical vapor deposition</article-title>. <source>Carbon N. Y.</source> <volume>42</volume>, <fpage>2867</fpage>&#x02013;<lpage>2872</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2004.06.035</pub-id></citation></ref>
<ref id="B163"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wang</surname> <given-names>X.</given-names></name> <name><surname>Zhi</surname> <given-names>L.</given-names></name> <name><surname>M&#x000FC;llen</surname> <given-names>K.</given-names></name></person-group> (<year>2008</year>). <article-title>Transparent, conductive graphene electrodes for dye-sensitized solar cells</article-title>. <source>Nano Lett.</source> <volume>8</volume>, <fpage>323</fpage>&#x02013;<lpage>327</lpage>.<pub-id pub-id-type="doi">10.1021/nl072838r</pub-id><pub-id pub-id-type="pmid">18069877</pub-id></citation></ref>
<ref id="B164"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wang</surname> <given-names>Y.</given-names></name> <name><surname>Zheng</surname> <given-names>Y.</given-names></name> <name><surname>Xu</surname> <given-names>X.</given-names></name> <name><surname>Dubuisson</surname> <given-names>E.</given-names></name> <name><surname>Bao</surname> <given-names>Q.</given-names></name> <name><surname>Lu</surname> <given-names>J.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Electrochemical delamination of CVD-grown graphene film: toward the recyclable use of copper catalyst</article-title>. <source>ACS Nano</source> <volume>5</volume>, <fpage>9927</fpage>&#x02013;<lpage>9933</lpage>.<pub-id pub-id-type="doi">10.1021/nn203700w</pub-id><pub-id pub-id-type="pmid">22034835</pub-id></citation></ref>
<ref id="B165"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wei</surname> <given-names>D.</given-names></name> <name><surname>Xu</surname> <given-names>X.</given-names></name></person-group> (<year>2012</year>). <article-title>Laser direct growth of graphene on silicon substrate</article-title>. <source>Appl. Phys. Lett.</source> <volume>100</volume>, <fpage>023110</fpage>.<pub-id pub-id-type="doi">10.1063/1.3675636</pub-id></citation></ref>
<ref id="B166"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wei</surname> <given-names>D.</given-names></name> <name><surname>Mitchell</surname> <given-names>J. I.</given-names></name> <name><surname>Tansarawiput</surname> <given-names>C.</given-names></name> <name><surname>Nam</surname> <given-names>W.</given-names></name> <name><surname>Qi</surname> <given-names>M.</given-names></name> <name><surname>Ye</surname> <given-names>P. D.</given-names></name> <etal/></person-group> (<year>2013</year>). <article-title>Laser direct synthesis of graphene on quartz</article-title>. <source>Carbon N. Y.</source> <volume>53</volume>, <fpage>374</fpage>&#x02013;<lpage>379</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2012.11.026</pub-id></citation></ref>
<ref id="B167"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wei</surname> <given-names>P.</given-names></name> <name><surname>Bao</surname> <given-names>W.</given-names></name> <name><surname>Pu</surname> <given-names>Y.</given-names></name> <name><surname>Lau</surname> <given-names>C. N.</given-names></name> <name><surname>Shi</surname> <given-names>J.</given-names></name></person-group> (<year>2009</year>). <article-title>Anomalous thermoelectric transport of dirac particles in graphene</article-title>. <source>Phys. Rev. Lett.</source> <volume>102</volume>, <fpage>166808</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.102.166808</pub-id><pub-id pub-id-type="pmid">19518743</pub-id></citation></ref>
<ref id="B169"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yan</surname> <given-names>Y.</given-names></name> <name><surname>Liang</surname> <given-names>Q.-F.</given-names></name> <name><surname>Zhao</surname> <given-names>H.</given-names></name> <name><surname>Wu</surname> <given-names>C.-Q.</given-names></name></person-group> (<year>2012</year>). <article-title>Thermoelectric properties of hexagonal graphene quantum dots</article-title>. <source>Phys. Lett. A</source> <volume>376</volume>, <fpage>1154</fpage>&#x02013;<lpage>1158</lpage>.<pub-id pub-id-type="doi">10.1016/j.physleta.2012.02.013</pub-id></citation></ref>
<ref id="B170"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yannopoulos</surname> <given-names>S. N.</given-names></name> <name><surname>Siokou</surname> <given-names>A.</given-names></name> <name><surname>Nasikas</surname> <given-names>N. K.</given-names></name> <name><surname>Dracopoulos</surname> <given-names>V.</given-names></name> <name><surname>Ravani</surname> <given-names>F.</given-names></name> <name><surname>Papatheodorou</surname> <given-names>G. N.</given-names></name></person-group> (<year>2012</year>). <article-title>CO2-Laser-induced growth of epitaxial graphene on 6H-SiC(0001)</article-title>. <source>Adv. Funct. Mater.</source> <volume>22</volume>, <fpage>113</fpage>&#x02013;<lpage>120</lpage>.<pub-id pub-id-type="doi">10.1002/adfm.201101413</pub-id></citation></ref>
<ref id="B171"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yin</surname> <given-names>J.</given-names></name> <name><surname>Wang</surname> <given-names>X.</given-names></name> <name><surname>Chang</surname> <given-names>R.</given-names></name> <name><surname>Zhao</surname> <given-names>X.</given-names></name></person-group> (<year>2012</year>). <article-title>Polyaniline decorated graphene sheet suspension with enhanced electrorheology</article-title>. <source>Soft Matter</source> <volume>8</volume>, <fpage>294</fpage>&#x02013;<lpage>297</lpage>.<pub-id pub-id-type="doi">10.1039/C1SM06728A</pub-id></citation></ref>
<ref id="B172"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yin</surname> <given-names>J.</given-names></name> <name><surname>Chang</surname> <given-names>R.</given-names></name> <name><surname>Kai</surname> <given-names>Y.</given-names></name> <name><surname>Zhao</surname> <given-names>X.</given-names></name></person-group> (<year>2013</year>). <article-title>Highly stable and AC electric field-activated electrorheological fluid based on mesoporous silica-coated graphene nanosheets</article-title>. <source>Soft Matter</source> <volume>9</volume>, <fpage>3910</fpage>&#x02013;<lpage>3914</lpage>.<pub-id pub-id-type="doi">10.1039/c3sm27835b</pub-id></citation></ref>
<ref id="B173"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yin</surname> <given-names>Z.</given-names></name> <name><surname>Wu</surname> <given-names>S.</given-names></name> <name><surname>Zhou</surname> <given-names>X.</given-names></name> <name><surname>Huang</surname> <given-names>X.</given-names></name> <name><surname>Zhang</surname> <given-names>Q.</given-names></name> <name><surname>Boey</surname> <given-names>F.</given-names></name> <etal/></person-group> (<year>2010</year>). <article-title>Electrochemical deposition of ZnO nanorods on transparent reduced graphene oxide electrodes for hybrid solar cells</article-title>. <source>Small</source> <volume>6</volume>, <fpage>307</fpage>&#x02013;<lpage>312</lpage>.<pub-id pub-id-type="doi">10.1002/smll.200901968</pub-id><pub-id pub-id-type="pmid">20039255</pub-id></citation></ref>
<ref id="B174"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yokomizo</surname> <given-names>Y.</given-names></name> <name><surname>Krishnamurthy</surname> <given-names>S.</given-names></name> <name><surname>Kamat</surname> <given-names>P. V.</given-names></name></person-group> (<year>2013</year>). <article-title>Photoinduced electron charge and discharge of graphene&#x02013;ZnO nanoparticle assembly</article-title>. <source>Catal. Today</source> <volume>199</volume>, <fpage>36</fpage>&#x02013;<lpage>41</lpage>.<pub-id pub-id-type="doi">10.1016/j.cattod.2012.04.045</pub-id></citation></ref>
<ref id="B175"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yu</surname> <given-names>H.</given-names></name> <name><surname>Wang</surname> <given-names>T.</given-names></name> <name><surname>Wen</surname> <given-names>B.</given-names></name> <name><surname>Lu</surname> <given-names>M.</given-names></name> <name><surname>Xu</surname> <given-names>Z.</given-names></name> <name><surname>Zhu</surname> <given-names>C.</given-names></name> <etal/></person-group> (<year>2012</year>). <article-title>Graphene/polyaniline nanorod arrays: synthesis and excellent electromagnetic absorption properties</article-title>. <source>J. Mater. Chem.</source> <volume>22</volume>, <fpage>21679</fpage>&#x02013;<lpage>21685</lpage>.<pub-id pub-id-type="doi">10.1039/c2jm34273a</pub-id></citation></ref>
<ref id="B176"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yu</surname> <given-names>Q.</given-names></name> <name><surname>Lian</surname> <given-names>J.</given-names></name> <name><surname>Siriponglert</surname> <given-names>S.</given-names></name> <name><surname>Li</surname> <given-names>H.</given-names></name> <name><surname>Chen</surname> <given-names>Y. P.</given-names></name> <name><surname>Pei</surname> <given-names>S.-S.</given-names></name></person-group>, (<year>2008</year>). <article-title>Graphene segregated on Ni surfaces and transferred to insulators</article-title>. <source>Appl. Phys. Lett.</source> <volume>93</volume>, <fpage>113103</fpage>.<pub-id pub-id-type="doi">10.1063/1.2982585</pub-id></citation></ref>
<ref id="B177"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yu</surname> <given-names>W. J.</given-names></name> <name><surname>Lee</surname> <given-names>S. Y.</given-names></name> <name><surname>Chae</surname> <given-names>S. H.</given-names></name> <name><surname>Perello</surname> <given-names>D.</given-names></name> <name><surname>Han</surname> <given-names>G. H.</given-names></name> <name><surname>Yun</surname> <given-names>M.</given-names></name> <etal/></person-group> (<year>2011</year>). <article-title>Small hysteresis nanocarbon-based integrated circuits on flexible and transparent plastic substrate</article-title>. <source>Nano Lett.</source> <volume>11</volume>, <fpage>1344</fpage>&#x02013;<lpage>1350</lpage>.<pub-id pub-id-type="doi">10.1021/nl104488z</pub-id><pub-id pub-id-type="pmid">21322606</pub-id></citation></ref>
<ref id="B178"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yuan</surname> <given-names>G.D.</given-names></name> <name><surname>Zhang</surname> <given-names>W.J.</given-names></name> <name><surname>Yang</surname> <given-names>Y.</given-names></name> <name><surname>Tang</surname> <given-names>Y.B.</given-names></name> <name><surname>Li</surname> <given-names>Y.Q.</given-names></name> <name><surname>Wang</surname> <given-names>J.X.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Graphene sheets via microwave chemical vapor deposition</article-title>. <source>Chem. Phys. Lett.</source> <volume>467</volume>, <fpage>361</fpage>&#x02013;<lpage>364</lpage>.<pub-id pub-id-type="doi">10.1016/j.cplett.2008.11.059</pub-id></citation></ref>
<ref id="B180"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>H.</given-names></name> <name><surname>Feng</surname> <given-names>P. X.</given-names></name></person-group> (<year>2014</year>). <article-title>Environmentally responsive graphene systems</article-title>. <source>Small</source> <volume>10</volume>, <fpage>2151</fpage>&#x02013;<lpage>2164</lpage>.<pub-id pub-id-type="doi">10.1002/smll.201303080</pub-id><pub-id pub-id-type="pmid">24376152</pub-id></citation></ref>
<ref id="B181"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>W. L.</given-names></name> <name><surname>Choi</surname> <given-names>H. J.</given-names></name></person-group> (<year>2014</year>). <article-title>Graphene oxide based smart fluids</article-title>. <source>Soft Matter</source> <volume>10</volume>, <fpage>6601</fpage>&#x02013;<lpage>6608</lpage>.<pub-id pub-id-type="doi">10.1039/c4sm01151a</pub-id><pub-id pub-id-type="pmid">25068905</pub-id></citation></ref>
<ref id="B182"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>W. L.</given-names></name> <name><surname>Liu</surname> <given-names>Y. D.</given-names></name> <name><surname>Choi</surname> <given-names>H. J.</given-names></name> <name><surname>Kim</surname> <given-names>S. G.</given-names></name></person-group> (<year>2012</year>). <article-title>Electrorheology of graphene oxide</article-title>. <source>ACS Appl. Mater. Interfaces</source> <volume>4</volume>, <fpage>2267</fpage>&#x02013;<lpage>2272</lpage>.<pub-id pub-id-type="doi">10.1021/am300267f</pub-id><pub-id pub-id-type="pmid">22476845</pub-id></citation></ref>
<ref id="B183"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>Y.</given-names></name> <name><surname>Tang</surname> <given-names>T. T.</given-names></name> <name><surname>Girit</surname> <given-names>C.</given-names></name> <name><surname>Hao</surname> <given-names>Z.</given-names></name> <name><surname>Martin</surname> <given-names>M. C.</given-names></name> <name><surname>Zettl</surname> <given-names>A.</given-names></name> <etal/></person-group> (<year>2009</year>). <article-title>Direct observation of a widely tunable bandgap in bilayer graphene</article-title>. <source>Nature</source> <volume>459</volume>, <fpage>820</fpage>&#x02013;<lpage>823</lpage>.<pub-id pub-id-type="doi">10.1038/nature08105</pub-id><pub-id pub-id-type="pmid">19516337</pub-id></citation></ref>
<ref id="B184"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>Y.</given-names></name> <name><surname>Tiwarya</surname> <given-names>P.</given-names></name> <name><surname>Scott Parenta</surname> <given-names>J.</given-names></name> <name><surname>Kontopoulou</surname> <given-names>M.</given-names></name></person-group> (<year>2013</year>). <article-title>Crystallization and foaming of coagent-modified polypropylene: nucleation effects of cross-linked nanoparticles</article-title>. <source>Polymer</source> <volume>54</volume>, <fpage>4814</fpage>&#x02013;<lpage>4819</lpage>.<pub-id pub-id-type="doi">10.1016/j.polymer.2013.07.020</pub-id></citation></ref>
<ref id="B185"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>Y.</given-names></name> <name><surname>Wu</surname> <given-names>S.</given-names></name> <name><surname>Wen</surname> <given-names>Y.-H.</given-names></name> <name><surname>Zhu</surname> <given-names>Z.</given-names></name></person-group> (<year>2010a</year>). <article-title>Surface-passivation-induced metallic and magnetic properties of ZnO graphitic sheet</article-title>. <source>Phys. Lett.</source> <volume>96</volume>, <fpage>223113</fpage>.<pub-id pub-id-type="doi">10.1063/1.3442507</pub-id></citation></ref>
<ref id="B179"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>H.</given-names></name> <name><surname>Feng</surname> <given-names>P. X.</given-names></name></person-group> (<year>2010b</year>). <article-title>Fabrication and characterization of few-layer graphene</article-title>. <source>Carbon N. Y.</source> <volume>48</volume>, <fpage>359</fpage>&#x02013;<lpage>364</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2009.09.037</pub-id></citation></ref>
<ref id="B186"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhang</surname> <given-names>W. L.</given-names></name> <name><surname>Park</surname> <given-names>B. J.</given-names></name> <name><surname>Choi</surname> <given-names>H. J.</given-names></name></person-group> (<year>2010c</year>). <article-title>Colloidal graphene oxide/polyaniline nanocomposite and its electrorheology</article-title>. <source>Chem. Commun.</source> <volume>46</volume>, <fpage>5596</fpage>&#x02013;<lpage>5598</lpage>.<pub-id pub-id-type="doi">10.1039/c0cc00557f</pub-id><pub-id pub-id-type="pmid">20577695</pub-id></citation></ref>
<ref id="B187"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhu</surname> <given-names>L.</given-names></name> <name><surname>Ma</surname> <given-names>R.</given-names></name> <name><surname>Sheng</surname> <given-names>L.</given-names></name> <name><surname>Liu</surname> <given-names>M.</given-names></name> <name><surname>Sheng</surname> <given-names>D. N.</given-names></name></person-group> (<year>2009</year>). <article-title>Thermopower and Nernst effect in graphene in a magnetic field</article-title>. <source>Phys. Rev. B</source> <volume>80</volume>, <fpage>081413</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevB.80.081413</pub-id><pub-id pub-id-type="pmid">20366904</pub-id></citation></ref>
<ref id="B188"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zhu</surname> <given-names>M.</given-names></name> <name><surname>Wang</surname> <given-names>J.</given-names></name> <name><surname>Holloway</surname> <given-names>B. C.</given-names></name> <name><surname>Outlaw</surname> <given-names>R. A.</given-names></name> <name><surname>Zhao</surname> <given-names>X.</given-names></name> <name><surname>Hou</surname> <given-names>K.</given-names></name> <etal/></person-group> (<year>2007</year>). <article-title>A mechanism for carbon nanosheet formation</article-title>. <source>Carbon N. Y.</source> <volume>45</volume>, <fpage>2229</fpage>&#x02013;<lpage>2234</lpage>.<pub-id pub-id-type="doi">10.1016/j.carbon.2007.06.017</pub-id></citation></ref>
<ref id="B189"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Zuev</surname> <given-names>Y. M.</given-names></name> <name><surname>Chang</surname> <given-names>W.</given-names></name> <name><surname>Kim</surname> <given-names>P.</given-names></name></person-group> (<year>2009</year>). <article-title>Thermoelectric and magnetothermoelectric transport measurements of graphene</article-title>. <source>Phys. Rev. Lett.</source> <volume>102</volume>, <fpage>096807</fpage>.<pub-id pub-id-type="doi">10.1103/PhysRevLett.102.096807</pub-id><pub-id pub-id-type="pmid">19392553</pub-id></citation></ref>
</ref-list>
<fn-group>
<fn id="fn1"><p><sup>1</sup>Space Technology missions directorate. The document is available at: <uri xlink:href="http://www.nasa.gov/directorates/spacetech/strg/2012_nstrf_rollins.html">http://www.nasa.gov/directorates/spacetech/strg/2012_nstrf_rollins.html</uri></p></fn>
</fn-group>
</back>
</article>