First-principles study on electronic and optical characteristics of zinc vanadate photocatalyst

There are some key requirements for a semiconductor employed as photo-catalyst in photoelectrochemical cells which can be predicted by density functional theory (DFT) calculations providing a robust framework to monitor electronic and optical properties. To explore the requiredcharacteristicsfor solar applications, we perform first-principles calculations based on DFT for Zn2V2O7structure. The results illustrate an upper valence band incorporating almost exclusively of O 2p orbitals, while V 3d states are the main constituents of the conduction band, with a moderate mobility of charge carriers. Furthermore, optical calculations display an indirect band gap with a value of 2.52 eV and a mean absorption coefficient about 7×104 cm-1 in the UV-Vis range.