Abstract
This work presents a comprehensive investigation of the van der Waals heterostructure (vdW-HS) composed of monolayers Ti2CO2 and MoGe2N4, exploring its potential for sustainable energy applications. The heterostructure exhibits a minimal lattice mismatch of approximately 0.3% between the constituent monolayers, ensuring coherent interfacing and structural compatibility. Phonon dispersion calculations confirm dynamic stability with no imaginary frequencies throughout the entire Brillouin zone. The AIMD simulations and elastic stiffness constants confirms the thermodynamic and mechanical stability of the vdW-HS Ti2CO2/MoGe2N4. Electronic structure analyses reveal that all stacking configurations yield identical band structures, characterized by an indirect band gap of 0.37 eV, as calculated using the Heyd−Scuseria−Ernzerhof (HSE06) functional with spin-orbit coupling. Notably, the vdW-HS exhibits a favorable type-II band alignment, promising for advanced optoelectronic applications. Furthermore, the valence band edge is suitably positioned to drive photocatalytic oxygen evolution reaction (OER), but not favorable for hydrogen evolution reaction (HER). The material also demonstrates a substantial static dielectric constant of 5.9, along with pronounced optical absorption in the visible spectrum and intense absorption of 1.4 × 106 cm-1 in the ultraviolet region. Importantly, the spectroscopic limited maximum efficiency (SLME) approaches ∼28.5%, surpassing that of several benchmark thin-film photovoltaic materials. These results underscore the promise of vdW-HS Ti2CO2/MoGe2N4 as a high-performance candidate for next-generation optical absorber material for green energy technologies.
Introduction
Two-dimensional (2D) materials have revolutionized the field of materials science and condensed matter physics, offering a versatile platform for next-generation energy devices. After the discovery of 2D materials such as graphene (Novoselov et al., 2016), phosphorene (Li et al., 2017), group-III chalcogenides (Mehta et al., 2023), and MXenes (Modi et al., 2023b; 2023a), 2D materials show excellent physicochemical properties, comprising large surface areas, high electrical conductivity, and tunable band structures, making them perfect for energy storage and conversion applications. Materials such as black phosphorus, transition metal dichalcogenides, and MXenes establish remarkably high carrier mobility and noticeable excitonic activities. These features allow their combination for diverse high-performance systems through photonics, electronics, sensing, biomedical technologies, and energy storage applications (; Li et al., 2024). Numerous schemes have been introduced in the past to modify the structural, electronic, and optical properties of 2D materials, including the application of strain, external electric field, introducing point-defects, and making heterostructures that regulate their distinctive limitations and improve their efficiency for real-world applications. However, these modifications come with certain challenges which limits their practical applications. For instance, achieving precise and uniform strain at the nanoscale level without introducing structural distortions (Robinson and Harder, 2009; Shi C. et al., 2024), and the effect of electric field is often hindered by screening effects by free charge carriers (Tepliakov et al., 2021). Likewise, the point-defects can lead to uncontrolled scattering of charge carrier which disturbs the carrier mobility (Lordi et al., 2010; Ma et al., 2025). The Van der Waals (vdW) heterostructures (HS) can address some of these limitations by stacking of two different monolayers, which enhance their properties and offer a flexible platform through interfacial coupling to overcome the drawbacks of individual monolayers and make high-performance electronic devices (Lan et al., 2022).
MXene-based 2D materials have attracted considerable attention owing to their tunable surface chemistry, high electrical conductivity, and mechanical robustness (Xiao et al., 2025). The controlled physical and surface variations of MXenes enhance their functionality for energy storage applications (Nasrin et al., 2022). The earliest member of the MXenes family, Ti3C2Tx nanosheets, was formed by exfoliation of Ti3AlC2 MAX phase in hydrofluoric acid at room temperature (Naguib et al., 2023). Subsequently, more than twenty different structures of the MXene materials have been synthesized successfully (Wang et al., 2024). The basic formula for MXenes material is Mn+1XnTx, where M is a transition metal (e.g., Ti, Zr, Hf, V, Nb), X denotes N and C, n is an integer ranging from one to four, and Tx represents the surface terminations such as F, OH or O (Shahzad et al., 2016; ; ). MXenes also permit different surface functionalization make them appropriate for numerous catalytic activities like oxygen reduction reaction (ORR), Hydrogen evolution reaction (HER), and oxygen evolution reaction (OER), etc., (Wang et al., 2021; ). The exclusive chemical and physical characteristics of MXenes make them appropriate for numerous functional applications like, electrodes for ion batteries, supercapacitors, sensors, photocatalysts, electrochemical catalysts, and hydrogen storage materials (; Wang et al., 2018; Pang et al., 2019). Ti2C holds the tinniest atomic layer structure among all MXene structures, thus providing a high surface area, that enhances its suitability for surface-active applications (). The electronic properties of Ti2C vary significantly with different functional groups, such as Ti2CF2, Ti2C(OH)2, and Ti2CO2 (; Li et al., 2025). Ti2CF2 and Ti2C(OH)2 illustrate the metallic behavior, while Ti2CO2 reveals semiconductor behavior (Kurtoglu et al., 2012; Li et al., 2020). So, O-functional group with Ti2C support for more applications, when making comparison with Ti2CF2 and Ti2C(OH)2 for photovoltaics (; ) and photo-sensing applications (Wojciechowski et al., 2019; ; Yu et al., 2021; Zhang et al., 2026).
On the other hand, the MoSi2N4 series was synthesized, which gained significant attention after the successful synthesis of MoSi2N4, which has a chemical formula of XA2Z4, where X denotes the transition metals, Z belongs to the elements of Group V, and A denotes the elements of Group IV (). It has a hexagonal lattice, containing seven atomic layers with a sequence of Z-A-Z-X-Z-A-Z, which shows an XA2 layer sandwiched in between two X-A bilayers (; Tian, 2025). Notably, the prediction of a new Janus MoSiGeN4 monolayer film with good stability, a suitable band edge position, and excellent light absorption ability suggests potential applications in various fields. The MoGe2N4 monolayer is characterized as an indirect semiconductor (Shao et al., 2024). MoGe2N4 are predicted to be promising candidates for optoelectronic and photocatalytic nanodevices owing to their strong light-matter interaction (Nguyen et al., 2021). Recently, MoGe2N4 has been heterostructure with WGe2N4 and MoSi2N4 has been designed with ultra-low polarization and exceptional photonic applications (Wu et al., 2025; Tarbool and Jappor, 2026). Similarly, Ti2CO2 has also been heterostructure with different 2D materials such as graphene and ZrSi2N4 among which Ti2CO2/ZrSi2N4 had shown remarkable performance as a prime candidate for photovoltaics (; Villagracia et al., 2026). Despite the fascinating physiochemical characteristics of individual monolayers of Ti2CO2 and MoGe2N4, notably the excellent chemical stability and surface-modifications of Ti2CO2 (Zhou et al., 2024), along with the robust mechanical and optoelectronic properties of MoGe2N4 (Nguyen and Pham, 2024), their integration into vdW-HS is unexplored. The combination of Ti2CO2 and MoGe2N4 into a vdW-HS is expected to yield synergistic effects, such as enhanced charge separation, tunable band alignment, and improved thermal resilience. A comprehensive understanding of the structural, electronic, and optical properties of the Ti2CO2/MoGe2N4 vdW-HS is essential to assess its viability for practical applications.
In this work, we employ first-principles density functional theory (DFT) calculations using the Vienna Ab initio Simulation Package (VASP) to investigate the structural, electronic, and optical properties of Ti2CO2/MoGe2N4 vdW-HS in various stacking configurations and disclose its potential for green energy applications.
Computational methodology
The first-principles calculations were performed by using VASP (Kresse and Furthmüller, 1996) along with the supplied Perdew-Burke-Ernzerhof (PBE) pseudopotentials (Perdew et al., 1996). The exchange-correlation effects were treated with the PBE generalized gradient approximation and the Heyd-Scuseria-Ernzerhof (HSE06) functional with and without spin-orbit coupling (SOC) to attain the precise band gap. A plane wave cutoff energy of 550 eV and Monkhorst–Pack k-point mesh grid of 9 × 9 × 1 (15 × 15 × 1) were utilized for the self-consistent (non-self-consistent) calculations. The DFT-D3 method of Grimme () was used to correct van der Waals interactions in vdW-HS Ti2CO2/MoGe2N4. Structural relaxation was carried out until the Hellmann−Feynman forces on all atoms dropped below 3 meV/Å and the total energy convergence reached between two consecutive self-consistent electronic cycles was less than 1 × 10−6 eV. An out-of-plane vacuum of 20 Å was added to prevent artifacts due to the periodic boundary conditions. The phonon dispersions were obtained with the Phonopy code (Togo and Tanaka, 2015) using a 5 × 5 × 1 supercell with 3 × 3 × 1 k-mesh. Thermal stability of the Ti2CO2/MoGe2N4 vdW-HS was further assessed via ab initio molecular dynamics (AIMD) simulations conducted at 300 K. These simulations utilized the same 5 × 5 × 1 supercell and were performed within the canonical ensemble (NVT) using the Nosé-Hoover thermostat, and simulations of a total time span of 7 ps.
Results and discussion
The optimized vdW-HS Ti2CO2/MoGe2N4 structures with all four AA-, AB-, AC-, and AD-stacking configurations are shown in Figure 1. All stacking configurations preserve the hexagonal phase symmetry, consistent with that of the individual monolayers comprising the heterostructure. The calculated lattice parameter for the AA-, AB-, AC-, and AD-stacking configurations is 3.01 Å. The calculated lattice parameters of 3.02 Å (Yin et al., 2023) for Ti2CO2 and 3.01 Å (Shao et al., 2024; Nguyen and Pham, 2024) for MoGe2N4 are in good agreement with the previously reported values, which suggest that our method for structural optimization is reliable. A slight lattice mismatch of ∼0.3% among the constituent monolayers signifies the vigorous lattice integrity, which is favorable for epitaxial growth and enables the formation of high-quality vdW-HS (). The lattice mismatch of ∼0.3% is lie in common accepted range for epitaxial growth, particularly for vdW-HS or thin films. However, there exist examples where the epitaxial growth has been achieved experimentally even at greater lattice mismatches (Xie et al., 2017). The binding energy of vdW-HS is calculated by using Equation 1 (Wei et al., 2026):where, the , and are the total energies of Ti2CO2/MoGe2N4 vdW-HS, Ti2CO2 and MoGe2N4 monolayers, respectively. The binding energies of all the AA-, AB-, AC-, and AD-stacking configurations are −0.27, −0.19, −0.27, and −0.28 eV, respectively. Negative values represent the energetical/interfacial stability of all the configurations (), but the AD-stacking configuration is more stable with its lowest ground state energy and binding energy. The maximum difference in the negative values of the ground state energies of the considered stacking configurations of vdW-HS Ti2CO2/MoGe2N4 is 90 meV.
FIGURE 1
The vdW forces are responsible for the interlayer interaction between the monolayers of vdW-HS Ti2CO2/MoGe2N4. The calculated equilibrium interlayer distance between the constituent monolayers ranges between 2.57 and 3.07 Å, which is comparable to conventional vdW-HS (Novoselov et al., 2016; Shi A. et al., 2024). The least equilibrium interlayer distance appears for the AD-stacking configuration, leading to stronger vdW interactions between the monolayers. Hence, the current study highlights the possibility of obtaining vdW-HS Ti2CO2/MoGe2N4 with uniform binding energies and relaxed structures.
The bonding behavior within the layers of Ti2CO2/MoGe2N4 vdW-HS of AD-stacking configurations has been investigated through the isosurface charge density difference (; Silvi and Savin, 1994). The charge redistribution at the interface (see Figure 2a) suggests that the two monolayers are connected by the vdW forces, which has been further confirmed from the Bader charge analysis followed by the Equation 2 (Nguyen et al., 2026);
FIGURE 2
The net charge transfer of 0.02 electron between the two monolayers from MoGe2N4 to Ti2CO2 confirms that no strong bonding exists at the interface the type of interaction is weak vdW interaction. During the charge redistribution process at the interface the depletion occurs from the Ge atom of MoGe2N4 and Ti atoms of Ti2CO2, while the accumulation of charges took place at N and O atoms at the interface. The averaged planer charge density along the z-axis shown in Figure 2b, describes the overall charge distribution along the z-axis, which shows that MoGe2N4 has higher charge density as compared to Ti2CO2. To additionally identify the charge transfer mechanism between Ti2CO2 and MoGe2N4 monolayers, the averaged planar charge density difference (see Figure 2c) along the z-axis is evaluated by using Equation 3 (Nguyen et al., 2026):where, ,, and are the averaged planar charge densities of Ti2CO2/MoGe2N4 vdW-HS and constituent monolayers, respectively. The positive peak represents the accumulation of charges at the interface near the oxygen atom of Ti2CO2, while the negative peak represents the depletion of charges from Ge atoms of MoGe2N4 near the interface. This result indicates that the electrons deplete from MoGe2N4 and accumulate at Ti2CO2, which facilitates the formation of a dipole. The oscillatory nature represents charge redistribution at the interface, which causes the interlayer coupling.
The mechanical stability of vdW-HS Ti2CO2/MoGe2N4 among all the considered stacking configurations has been confirmed by evaluating fundamental elastic stiffness constants and elastic moduli, including the shear modulus, bulk modulus, Young’s modulus, and Poisson’s ratio. As summarized in Table 1, the calculated elastic constants satisfy the Born-Huang stability conditions for 2D materials (C11 > 0, C11>|C12|, C66=(C11-C12)/2) (; Wang et al., 2022), which confirm that all the considered stacking configurations of vdW-HS Ti2CO2/MoGe2N4 are mechanically stable (Naimi et al., 2025). Furthermore, for all stacking configurations, the value of Poisson’s ratio is lower than 0.5, consistent with prior studies on stable materials (Lee et al., 2018; ), thus validating the structural robustness of all the stacking configurations. The mechanical stability of the heterostructure across all stacking configurations, as evidenced by the properties summarized in Table 1, confirms its structural robustness and supports its suitability for advanced technological applications ().
TABLE 1
| Parameters | AA | AB | AC | AD |
|---|---|---|---|---|
| a (Å) | 3.01 | 3.01 | 3.01 | 3.01 |
| dl (Å) | 2.62 | 3.07 | 2.61 | 2.57 |
| Eb (eV) | −0.27 | −0.19 | −0.27 | −0.28 |
| C11 | 720 | 726 | 716 | 712 |
| C12 | 219 | 218 | 216 | 213 |
| C66 | 250 | 253 | 249 | 249 |
| K (N/m) | 470 | 472 | 466 | 463 |
| E (N/m) | 653 | 660 | 651 | 648 |
| G (N/m) | 250 | 253 | 249 | 249 |
| v | 0.3 | 0.3 | 0.3 | 0.3 |
Calculated lattice parameter a (Å), interlayer distance dl (Å), binding energy Eb (eV), elastic stiffness constants, bulk modulus K (N/m), Young’s modulus E (N/m), shear modulus G (N/m), and Poisson’s Ratio v of all considered stacking configurations of vdW-HS Ti2CO2/MoGe2N4.
The phonon spectrum of AD-stacking configuration of vdW-HS Ti2CO2/MoGe2N4 is presented in Figure 3a, which depicts no negative frequency over the entire Brillouin zone, demonstrating its dynamic stability. The significant phonon hybridization between acoustic and low-lying optical phonon modes indicates reduced lattice thermal conductivity of vdW-HS Ti2CO2/MoGe2N4, highlighting its promise for thermoelectric applications. Figure 3b demonstrates the energy profile attained from AIMD simulations for AD-stacking vdW-HS Ti2CO2/MoGe2N4, where low energy fluctuations prove its thermal stability at 300 K. After a distinguish equilibrium phase, the total energy becomes stable with minimum variations after 5 ps duration, demonstrating a well-preserved structure. Structural resemblance between pre- and post-AIMD simulations confirms the thermal stability of the heterostructure.
FIGURE 3
Figure 4 represents the electronic band characteristics of all AA-, AB-, AC-, and AD-stacking configurations of the Ti2CO2/MoGe2N4 vdW-HS, comprising an indirect band gap of 0.13 eV (with SOC) and 0.14 eV (without SOC) at the PBE level. SOC leads the considerable band splitting of 137 meV at the K-point for the top two valence bands. Remarkably, the occurrence of an indirect band gap, with valence band maxima (VBM) at the Γ-point and conduction band minima (CBM) at the M-point, confirms the semiconducting nature of the considered vdW-HS which is a key requirement for optoelectronic devices. Furthermore, the indirect bandgap semiconductor outperforms due to the phonon assisted transitions and extended carrier lifetime making them favorable for optoelectronic applications (Kang et al., 2019; ; Malyi and Acosta, 2020; Kangsabanik et al., 2022; ; Zakay et al., 2023). The indistinguishable structural and electronic characteristics for all the stacking configurations of vdW-HS Ti2CO2/MoGe2N4 suggest a consistent behavior for all the stacking configurations. Since the AD-stacking configuration in energetically more favorable, the subsequent analysis has been proceeded with for this configuration.
FIGURE 4
As the PBE functional underestimates the band gap values (Shi A. et al., 2024), the hybrid functional HSE06 with SOC has been utilized for accurate band gap calculations, and the outcomes are presented in Figure 5. The calculated band gap turns out to be 0.37 eV with an identical splitting trend compared to that observed at the PBE-SOC. The band gap of the heterostructure is reduced as compared to the constituent monolayers Ti2CO2 (0.89 eV ()) and MoGe2N4 (1.41 eV (Shao et al., 2024)), which provides higher intrinsic conductivity. The density of states (DOS) examination reveals that the CBM is mostly comprised of Ti d-states, while the VBM mainly arises from Mo d-states. Moreover, O p-states also contributes to the CBM, and N p-states to the VBM. Notably, hybridization in observed between Ti d- and O p-states in the conduction band, whereas Mo d- and N p- states exhibit hybridization in the valence band side.
FIGURE 5
Figure 6 confirms that vdW-HS Ti2CO2/MoGe2N4 shows the type-II band alignment, such that the MoGe2N4 and Ti2CO2 form CBM and VBM, respectively, resulting in directional electron transport originating from Ti2CO2. This type of band alignment assists charge carrier separation at the interface of band edges through underestimating the spatial coincidence of holes and electrons, which is beneficial for optoelectronics applications, like photodetectors (Xiong and Yang, 2023; Singh et al., 2024). Moreover, such a feature would lead to enhance the efficiency, presenting the vdW-HS Ti2CO2/MoGe2N4 as a perfect applicant for energy conversion and light harvesting.
FIGURE 6
The band edges are one of the benchmarks to identify the compatibility of a material to accomplish water splitting by photocatalysis. To do so, the CBM must lie above the hydrogen evolution potential (−4.50 eV), and the VBM must be located at a lower energy than the oxygen evolution potential (−5.73 eV) relative to the vacuum level (Singh-Miller and Marzari, 2009; Zheng et al., 2018; ; Nguyen et al., 2026). To determine CBM and VBM positioning, the vacuum level has been determined from the planar-averaged electrostatic potential profile along the z-direction. The CBM and VBM energies were then aligned with respect to this vacuum level to obtain their absolute band positions (EVBM-abs and ECBM-abs) followed by Equations 4, 5 (Kahn, 2016; ).here, Evac, EVBM-abs, ECBM-abs, EVBM and Eg are the vacuum level, valance band with respect to vacuum level, conduction band with respect to vacuum level, eigen value of valance band and bandgap calculated from HSE06-SOC calculation. This method is standard for evaluating the photocatalytic water splitting potential of 2D materials, as it allows direct comparison with the redox potentials of water. Our evaluated band edge positions at −5.82 eV for the valence band edge and −5.46 eV for the conduction band edge demonstrate that vdW-HS Ti2CO2/MoGe2N4 is not suitable for photocatalytic HER but is obviously effective for oxidation of H2O to O2. The photogenerated electrons does not acquire sufficient energy to reduce protons into hydrogen, whereas the photogenerated holes have adequate potential to oxidize water into oxygen, thus allowing the photocatalytic OER (). The small band gap simply means the material absorbs lower energy photons, which does not compromise its ability to oxidize water as long as photogenerated holes have sufficient energy.
Lastly, the optical response of vdW-HS Ti2CO2/MoGe2N4 has been investigated using the Kramers–Kronig relations (Vittoria, 1993; ; Mumtaz et al., 2024). Figure 7a demonstrates the real (ε1) and imaginary (ε2) parts of the dielectric function. The static dielectric constant, defined as ε1 at zero frequency, is 5.90, disclosing a notably strong electronic polarizability of the heterostructure. A pronounced peak in ε1 occurs at 1.80 eV, corresponding to maximum polarization near the onset of the visible region. Within visible energy spectra, moderate polarization exists that gradually decreases with increasing photon energy. In contrast, metallic behavior emerges in the ultraviolet (UV) region, as evidenced by the negative ε1 values beyond 9.30 eV (Sun et al., 2022). The imaginary part ε2 demonstrates the absorptive nature of the vdW-HS Ti2CO2/MoGe2N4, due to the inter-band transitions occurring in the semiconducting vdW-HS, as observed in the PDOS, these inter-band transitions must be from Mo-d to Ti-d state. The highest ε2 peak resides at 3.30 eV, after which it decreases, and so does the intensity of interband transitions.
FIGURE 7
The absorption coefficient can be calculated by using the Equation 6 (Nguyen et al., 2026):where, c is the speed of light in vacuum and is the dielectric coefficient. Figure 7b explains the absorption spectrum of vdW-HS Ti2CO2/MoGe2N4, revealing an adsorption coefficient of 5 × 105 cm-1 in the visible region at 3.30 eV. The highest intensity of absorption happens in the UV region at 1.4 × 106 cm-1 at 9.50 eV. Therefore, the absorption along visible and UV light is consistent for the generation of electron-hole pairs. Absorption starts approximately at 0.90 eV, corresponding to the optical band gap of vdW-HS Ti2CO2/MoGe2N4. With a wide absorption range, the vdW-HS Ti2CO2/MoGe2N4 is extremely suitable for photodetector and solar cell applications.
Spectroscopic Limited Maximum Efficiency (SLME) is the ratio between the maximum power density Pmax and the incident photon power density Pin as Equation 7:where, Jsc, J0, e, V, k and T are the short-circuit current density, the reverse saturation current density, charge of electron, potential across the absorber material, Boltzmann constant and temperature, respectively (Yu and Zunger, 2012; ). Figure 7c shows the SLME of vdW-HS Ti2CO2/MoGe2N4 as a function of material thickness (µm). It provides an effective metric for estimating solar cell performance and is strongly governed by the band gap and optical absorption of a material (Singh and Ahuja, 2022). It increases gradually with increasing material and approaches saturation near 5 μm, where it attains the peak value of 28.5%. This maximum SLME value is comparable to that of established photovoltaic materials, such as silicon-based crystals (Lee et al., 2014), silicon superlattices (Oh et al., 2015), and widely used thin film absorbers like CdTe ∼31.5% and CuInSe2 ∼28% (Sharan et al., 2022). These features describe that vdW-HS Ti2CO2/MoGe2N4 holds a great potential as an efficient photovoltaic absorber, making it a promising candidate for next-generation solar energy technologies.
Conclusion
A comprehensive study on vdW-HS Ti2CO2/MoGe2N4 has been conducted such that among all the stacking configurations, the AD-stacking configuration is energetically more favorable with the lowest ground state and binding energies. The charge redistribution occurred at the interface and very minimal chare transfer of 0.02 electron from MoGe2N4 to Ti2CO2 occurred which demonstrates that the type of interaction is weak vdW interaction. The absence of imaginary modes across the entire Brillouin zone in phonon spectra and minimal energy fluctuations in the AIMD calculations confirm the dynamic and thermodynamic stability of the AD-stacking configuration, respectively. The considered vdW-HS satisfied the Born-Huang stability conditions which confirms its mechanical stability. Electronic structure calculations reveal an indirect band gap of 0.37 eV at the HSE06-SOC level. The heterostructure displays type-II band alignment, promoting efficient separation of photoexcited electron-hole pairs. The obtained band edges relative to the vacuum level reveal that the studied material favors photocatalytic OER while being unfavorable for HER. Additionally, vdW-HS Ti2CO2/MoGe2N4 demonstrates strong absorption in the visible region and exceptionally high absorption in the ultraviolet region. With an SLME of ∼28.5%, the heterostructure outperforms many leading thin-film photovoltaic absorbers. These findings, collectively, position vdW-HS Ti2CO2/MoGe2N4 as a promising material for renewable energy applications.
Statements
Data availability statement
The original contributions presented in the study are included in the article. Further inquiries can be directed to the corresponding author.
Author contributions
UM: Formal Analysis, Writing – original draft, Visualization, Writing – review and editing, Investigation, Conceptualization, Methodology, Data curation. YD: Validation, Visualization, Formal Analysis, Data curation, Writing – review and editing, Investigation. MS: Software, Resources, Validation, Supervision, Project administration, Conceptualization, Writing – review and editing.
Funding
The author(s) declared that financial support was received for this work and/or its publication. MS acknowledges financial support provided by the Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute. MS and UM are grateful for access to the University of Nottingham Ningbo China High Performance Computing Facility.
Conflict of interest
The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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The author(s) declared that generative AI was not used in the creation of this manuscript.
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Summary
Keywords
MoGe2N4, MXene, oxygen evolution reaction, SLME, vdW-heterostructure
Citation
Mumtaz U, Ding Y and Sajjad M (2026) Type-II band alignment and high spectroscopic-limited efficiency in Ti2CO2/MoGe2N4 van der Waals heterostructure. Front. Nanotechnol. 8:1812144. doi: 10.3389/fnano.2026.1812144
Received
16 February 2026
Revised
07 April 2026
Accepted
09 April 2026
Published
15 May 2026
Volume
8 - 2026
Edited by
Mojtaba Mohammadi, Toyota Technological Institute, Japan
Reviewed by
Shifa Wang, Chongqing Three Gorges University, China
Salma Naimi, Mohammed V University, Morocco
Updates
Copyright
© 2026 Mumtaz, Ding and Sajjad.
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*Correspondence: Muhammad Sajjad, muhammad.sajjad@nottingham.edu.cn
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