Investigation of structural, electronic and optical properties of (V+P)-doped BaZrO3 for photocatalytic applications using density functional theory

Abstract

In the present study, we employ spin-polarized density functional theory for examining changes in the opto-electronic properties of wide band gap barium zirconate by incorporating Vanadium and Phosphorous dopants at Zr- and O-sites of BaZrO3, respectively. The generalized gradient approximation is used to compute thermodynamic and structural properties, while modified Becke-Johnson local density approximation is employed for the electronic and optical properties of pristine, mono-doped (V- or P-doped) and co-doped ((V + P)-doped) BaZrO3. The doping of a P atom at a O-site is found to cause shift in the valence band toward the conduction band; giving rise to an acceptor system with reduced band gap as compared to pristine BaZrO3. On the other hand, doping of V atom at a Zr-site leads to a donor system which modulates the conduction band of pristine BaZrO3. The charge compensated co-doping of V and P at neighboring Zr-site and O-site results in a band gap reduction of pristine BaZrO3 and is found to be suitable for absorbing solar radiations in the visible region of electromagnetic spectrum. The calculated electronic and optical properties of (V + P)-doped BaZrO3 together with positioning of the conduction and valence band edges with respect to water oxidation and reduction potentials make this material a potential candidate for hydrogen production through photocatalysis of water using solar radiations.