Photocatalytic activity of V2O5/ZnV2O6 catalysts and its origin: Insights into enhanced photocatalytic mechanisms via DFT study

Abstract

The selective catalytic reduction (SCR) catalyst based on ZnV2O6 is primarily utilized for photocatalytic CO2 reduction and organic compound degradation. It's crucial to understand the catalytic performance of V2O5/ZnV2O6(001) before developing improved SCR catalysts. On the surface of ZnV2O6 (001), three potential SCR catalyst models were built utilizing linear V2O5 and cyclic V2O5, respectively. Density functional theory was used to investigate the electronic structure and catalytic mechanism of the aforesaid catalysts (DFT). The findings show that by inserting the V2O5 cluster, the ZnV2O6 (001) energy band structure may be modulated in a controlled manner. V-3d mostly contributes to the conduction band around the Fermi level, while O-2p primarily contributes to the valence band. The comprehensive analysis of energy band, the density of states, and interface electron interaction shows that compared with single ZnV2O6, This V2O5/ZnV2O6(001) model can realize the efficient separation of photogenerated carriers and has good redox ability. Therefore, V2O5/ZnV2O6 (001) model has been proved to be an excellent photocatalyst in theory. This work is helpful to understand the effect of V2O5 modification on the photocatalytic activity of ZnV2O6 and provides a theoretical basis for the design of other vanadate high-performance catalysts.