Editorial: Photocatalysis for Environmental Applications
- 1Chongqing Key Laboratory of Catalysis and New Environmental Materials, Engineering Research Center for Waste Oil Recovery Technology and Equipment of Ministry of Education, College of Environment and Resources, Chongqing Technology and Business University, Chongqing, China
- 2Research Center for Environmental Science & Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, China
- 3College of Materials Science and Engineering, Chongqing University, Chongqing, China
- 4Department of Chemistry, University of Virginia, Charlottesville, VA, United States
Editorial on the Research Topic
Photocatalysis for Environmental Applications
Environmental pollution is one of the major challenges because of the rapid development of urbanization and industrialization. Considering this environmental challenge, providing a clean environment for human beings is very important for the sustainability. The nanostructured photocatalysts with intriguing physiochemical property have offered opportunities to solve the issue of environmental sustainability (Chen et al., 2019; Huo et al., 2019; Li J. et al., 2019). In recent years, significant advances have been witnessed on the synthesis and application of photocatalyst in environmental remediation (He et al., 2018a; Li et al., 2018c; Li X. et al., 2018, 2019; Wang et al., 2018c). These new photocatalysts have enabled wide applications in the air purification, wastewater treatment, and so on (Cui et al., 2018; He et al., 2018b; Li et al., 2018b; Xiong et al., 2018) The rapid development in catalysis science, nanoscience, and materials enable the significant advances in new strategies for the controlled preparation, photocatalysis reaction mechanism, and structure-activity relationship of photocatalysts (Dong et al., 2018a; Li et al., 2018a; Wang et al., 2018a,b). The structural features of photocatalysts can be further tuned to achieve enhanced photocatalytic performance in environmental applications (Dong et al., 2018b; Li X. et al., 2018; Wang et al., 2018d).
The rapid development in photocatalysis for environment has inspired this interesting Research Topic. We have invited scientists worldwide to contribute original research and review articles which could enhance our understanding of the key problems in environmental applications of nanostructured photocatalysts. The original articles describing the photocatalysts for environmental control, and for sustainable development have been accepted for publication after peered review. In this topic issue, the readers will find very interesting results covering the following aspects (1) design and synthesis of photocatalysts with new morphology and active catalytic sites; (2) photocatalysts for green synthesis; (3) photocatalysts for CO2 conversion to solar fules; (4) photocatalysts for wastewater treatment and air purification; and (5) revealing the photocatalysis reaction mechanism as applied in environmental problems.
For the g-C3N4 based photocatalysts, Guan et al. synthesized Ti4O7/g-C3N4 composites by a low temperature method. The enhanced photocatalytic activity for Ti4O7/g-C3N4 could be ascribed to the promoted charge separation and photoabsorption efficiency. Yang et al. fabricated a monolithic g-C3N4/melamine sponge by a cost-effective ultrasonic-coating method. The monolithic g-C3N4/melamine demonstrated high photocatalytic activity for NO removal and CO2 reduction. Guan et al. prepared the Ti4O7/g-C3N4 photocatalysts by a hydrolysis method. The Ti4O7/g-C3N4 exhibited remarkably improved photocatalytic activity for hypophosphite oxidation, which can be ascribed to the heterojunction structure of Ti4O7/g-C3N4 that enhanced charge carrier efficiency (Guan et al.).
Xu et al. prepared BiVO4 by a facile method and conducted a trapping experiment to study the free radical transformation mechanisms. They identified •OH and h+ as the main active radicals for oxidation. Han et al. developed a new photoelectrochemical (PEC) technology for simultaneous SO2 removal and H2 production. The enhanced H2 production and SO2 removal efficiency can be attributed to the improved charge carrier transfer after Mo doping (Han et al.). Regmi et al. reviewed recent advances on the microbial decontamination by photocatalysts and their possible mechanisms are highlighted.
Cui et al. fabricated the Ag3PO4/MoS2 nanocomposites and revealed that the improved performance of Ag3PO4/MoS2 can be ascribed to wide spectra response, efficient charge separation and enhanced oxidation capacity. He et al. developed a two-step ZnO-modified strategy to immobilize the catalyst on rGO sheets. The high ammonia degradation efficiency of ZnO/Cu/rGO can be attributed to the enhanced ROSs production efficiency and the activated interfacial catalytic sites. Shi et al. prepare high energy faceted TiO2 nanosheets by calcination of TiOF2 cubes. The 500°C-calcined sample exhibits the highest photocatalytic activity for removal of acetone owing to the high energy TiO2-NSs and the surface adsorbed fluorine.
Kim et al. synthesized the nitrogen doped TiO2 by a novel plasma electrolysis method. The 0.4 at.% N doped TiO2 catalyst showed the highest photocatalytic performance. Xu et al. developed a BiOCl/NaNbO3 p-n heterojunction by an in-situ method. The BiOCl/NaNbO3 composites exhibited much enhanced photocatalytic activity attributed to the formation of p-n junction between NaNbO3 and BiOCl that facilitated the charge separation (Xu et al.). Ren et al. synthesized the AgBr@Ag modified titanium phosphate composites. The AgBr@Ag/titanium phosphate exhibited higher photocatalytic activity and the photocatalytic degradation mechanisms were proposed.
She et al. reported selective activation of saturated C–H bond to generate the high-value-added chemicals on Ni-doped CdS nanoparticles. The high photocatalytic performance can be attributed to the cubic and hexagonal phases, Ni-doping and the charge carriers separation. Li et al. synthesized Au/BiFeO3 homojunctions via a simple method. The Au1.2-BFO showed efficient photocatalytic activity due to the hierarchical structure, SPR effect of Au particles, and the defects (Li et al.). Zhang and Liang fabricated the new 2D g-C3N4@BiOCl/Bi12O17Cl2 by a facile approach, which showed enhanced visible light absorption and electron-hole separation efficiency and thus highly enhanced photocatalytic activity for NO removal.
At last, as the Guest Editors of this topic issue, we would like to appreciate all the authors for the contributed articles and thank for all the referees for their comments on the manuscripts. We hope that the readers will find the results in articles of this topic issue interesting and useful for their research. Finally, we appreciate the editorial staff of Frontiers in Chemistry for their work in publishing of this topic issue.
All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.
Conflict of Interest Statement
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.
Chen, P., Wang, H., Liu, H., Ni, Z., Li, J., Zhou, Y., et al. (2019). Directional electron delivery and enhanced reactants activation enable efficient photocatalytic air purification on amorphous carbon nitride Co-Functionalized with O/La. Appl. Catal. B Environ. 242, 19–30. doi: 10.1016/j.apcatb.2018.09.078
Cui, W., Li, J., Sun, Y., Wang, H., Jiang, G., Lee, S., et al. (2018). Enhancing ROS generation and suppressing toxic intermediate production inphotocatalytic NO oxidation on O/Ba co-functionalized amorphous carbon nitride. Appl. Catal. B Environ. 237, 938–946. doi: 10.1016/j.apcatb.2018.06.071
Dong, X., Li, J., Xing, Q., Zhou, Y., Huang, H., and Dong, F. (2018a). The activation of reactants and intermediates promotes the selective photocatalytic NO conversion on electron-localized Sr-intercalated g-C3N4. Appl. Catal. B Environ. 232, 69–76. doi: 10.1016/j.apcatb.2018.03.054
Dong, X., Zhang, W., Sun, Y., Li, J., Cen, W., Cui, Z., et al. (2018b). Visible light induced charge transfer pathway and photocatalysis mechanism on Bi semimetal@defective BiOBr hierarchical microspheres. J. Catal. 357, 41–50. doi: 10.1016/j.jcat.2017.10.004
He, W., Sun, Y., Jiang, G., Huang, H., Zhang, X., and Dong, F. (2018b). Activation of amorphous Bi2WO6 with synchronous Bi metal and Bi2O3 coupling: photocatalysis mechanism and reaction pathway. Appl. Catal. B Environ. 232, 340–347. doi: 10.1016/j.apcatb.2018.03.047
He, W., Sun, Y., Jiang, G., Li, Y., Zhang, X., Zhang, Y., et al. (2018a). Defective Bi4MoO9/Bi metal core/shell heterostructure: enhanced visible light photocatalysis and reaction mechanism. Appl. Catal. B Environ. 239, 619–627. doi: 10.1016/j.apcatb.2018.08.064
Huo, W., Dong, X., Li, J., Liu, M., Liu, X., Zhang, Y., et al. (2019). Synthesis of Bi2WO6 with gradient oxygen vacancies for highly photocatalytic NO oxidation and mechanism study. Chem. Eng. J. 361, 129–138. doi: 10.1016/j.cej.2018.12.071
Li, J., Dong, X., Sun, Y., Cen, W., and Dong, F. (2018a). Facet-dependent interfacial charge separation and transfer in plasmonic photocatalysts, Appl. Catal. B Environ. 226, 269–277. doi: 10.1016/j.apcatb.2017.12.057
Li, J., Dong, X., Sun, Y., Jiang, G., Chu, Y., Lee, S., et al. (2018b). Tailoring the rate-determining step in photocatalysis via localized excess electrons for efficient and safe air cleaning. Appl. Catal. B Environ. 239, 187–195. doi: 10.1016/j.apcatb.2018.08.019
Li, J., Zhang, W., Ran, M., Sun, Y., Huang, H., and Dong, F. (2019). Synergistic integration of Bi metal and phosphate defects on hexagonal and monoclinic BiPO4: enhanced photocatalysis and reaction mechanism. Appl. Catal. B Environ. 243, 313–321. doi: 10.1016/j.apcatb.2018.10.055
Li, J., Zhang, Z., Cui, W., Wang, H., Cen, W., Johnson, G., et al. (2018c). The spatially oriented charge flow and photocatalysis mechanism on internal van der waals heterostructures enhanced g-C3N4. ACS Catal. 8, 8376–8385. doi: 10.1021/acscatal.8b02459
Li, X., Zhang, W., Cui, W., Sun, Y., Jiang, G., Zhang, Y., et al. (2018). Bismuth Spheres Assembled on Graphene Oxide: Directional Charge Transfer Enhances Plasmonic Photocatalysis and In Situ DRIFTS Studies. Appl. Catal. B Environ. 221, 482–489. doi: 10.1016/j.apcatb.2017.09.046
Li, X., Zhang, W., Li, J., Jiang, G., Zhou, Y., Lee, S., et al. (2019). Transformation pathway and toxic intermediates inhibition of photocatalytic NO removal on designed Bi metal@defective Bi2O2SiO3, Appl. Catal. B Environ. 241, 187–195. doi: 10.1016/j.apcatb.2018.09.032
Wang, H., He, W., Dong, X., Wang, H., and Dong, F. (2018a). In situ FT-IR investigation on the reaction mechanism of visible light photocatalytic NO oxidation with defective g-C3N4. Sci. Bull. 63,117–125. doi: 10.1016/j.scib.2017.12.013
Wang, H., Sun, Y., He, W., Zhou, Y., Lee, S., and Dong, F. (2018c). Visible light induced electrons transfer from semiconductor to insulator enables efficient photocatalytic activity on insulator-based heterojunctions. Nanoscale 10, 15513–15520. doi: 10.1039/C8NR03845G
Wang, H., Sun, Y., Jiang, G., Zhang, Y., Huang, H., Wu, Z., et al. (2018b). Unraveling the mechanisms of visible light photocatalytic NO purification on earth-abundant insulator-based core-shell heterojunctions. Environ. Sci. Technol. 52, 1479–1487. doi: 10.1021/acs.est.7b05457
Wang, H., Zhang, W., Li, X., Li, J., Cen, W., Li, Q., et al. (2018d). Highly enhanced visible light photocatalysis and in situ FT-IR studies on Bi metal@defective BiOCl hierarchical microspheres. Appl. Catal. B Environ. 225, 218–227. doi: 10.1016/j.apcatb.2017.11.079
Keywords: photocatalysis, environmental catalysis, air pollution, reaction mechanism, nanomaterials
Citation: Dong F, Zhang Y and Zhang S (2019) Editorial: Photocatalysis for Environmental Applications. Front. Chem. 7:303. doi: 10.3389/fchem.2019.00303
Received: 12 February 2019; Accepted: 16 April 2019;
Published: 01 May 2019.
Edited by:Simelys Hernández, Polytechnic University of Turin, Italy
Reviewed by:Fatwa Abdi, Helmholtz-Zentrum Berlin für Materialien und Energie, Helmholtz-Gemeinschaft Deutscher Forschungszentren (HZ), Germany
Copyright © 2019 Dong, Zhang and Zhang. 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) and the copyright owner(s) 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.