Electronic and photocatalytic properties of ZnO/GaTe heterostructure from first principles calculations

Constructing a novel van der Waals (vdW) heterostructure by integrating diverse two-dimensional (2D) materials is significant to generate the more fascinating performances. In this present contribution, the electronic and photocatalytic properties of ZnO/GaTe heterostructure have been explored using first-principles calculations. The results reveal that the interaction between layers is dominated by the vdW forces. It displays an intrinsic type-II band alignment and a direct band gap of 1.730 eV under hybrid HSE06 functional. The valence band top and conduction band bottom are located at ZnO and GaTe layers, respectively, which guarantees the spatial separation of photogenerated electron-hole pairs and improves the photocatalytic efficiency. Moreover, the band edges all span the energy levels of both the reduction and oxidation potentials of H2O, indicating that its better photocatalytic performance. The modulated photocatalytic properties under varied pH circumstances imply that an acid environment is more favorable to the water splitting process. Furthermore, the band edge alignment exhibits the significant adjustability through varying vertical and in-plane biaxial strains. These theoretical findings indicate that the ZnO/GaTe heterostructure can offer an alternative strategy to design the efficient photocatalysts for water splitting.

Automated summary

In this study, the electronic and photocatalytic properties of ZnO/GaTe heterostructure were investigated using first-principles calculations. The results showed an intrinsic type-II band alignment and a direct band gap of 1.730 eV, with the valence band top and conduction band bottom located at ZnO and GaTe layers, respectively. This design ensures efficient spatial separation of photogenerated electron-hole pairs and improved photocatalytic efficiency. Additionally, the band edges align with the reduction and oxidation potentials of H2O, indicating better photocatalytic performance. The modulated photocatalytic properties under different pH conditions suggest that an acidic environment favors the water splitting process. The band edge alignment can be adjusted through vertical and in-plane biaxial strains, making the ZnO/GaTe heterostructure a potential alternative for efficient photocatalysts in water splitting applications.