Layered perovskite Sr2Ta2O7 for visible light photocatalysis: A first principles study

Abstract

The layered perovskite Sr2Ta2O7 has been investigated for efficient visible light photocatalysis using the first principles study. The electronic structure of Sr2Ta2O 7 is tuned by the anionic (N)/cationic (Mo, W) mono- and co-doping. Such doping creates impurity states in the band gap and therefore reduces the band gap significantly. The absolute band edge position of the doped Sr 2Ta2O7 with respect to the water oxidation/reduction potential depends a lot on the p/d-orbital's energies of anionic/cationic dopants, respectively. The stability of the co-doped system is governed by the Coulomb interactions and charge compensation effects. © 2013 American Chemical Society.