Band gap Engineering of ZnO via transition metal Doping: An ab initio study

Ab initio density functional theory calculations are performed to calculate the electronic and optical properties of transition metal doped ZnO, in order to achieve optimum bandgap reduction required for a potential photocatalyst. Geometry optimization analysis reveals that Fe, Cr, Mn and Nb doped systems are the most stable structures among our studied materials, which are further investigated for their aforementioned properties. The analysis of the Cr doped system show the maximum decrease in the bandgap and a red shift toward the visible region due to the valence electrons, suggesting that Cr doped ZnO is substantially a promising photocatalytic material for dye degradation applications.