Role of P in improving V-doped SrTiO3 visible light photocatalytic activity for water splitting: A first - Principles study

In this work, the +3-valent P-doped SrTiO3 has been shown for the first time to be theoretically achievable and to improve the photocatalytic performance of SrTiO3 in co-doping with metal ions. The effects of P and V doping on the electronic structure, optical properties and photocatalytic activity of the SrTiO3 system were systematically investigated using a first-principles calculation method. The results show that when V is singly doped with SrTiO3, although the band gap width is greatly reduced and the optical absorption performance is significantly enhanced, it is difficult to photocatalytic split water for hydrogen production due to the high VBM. When one electron provided by +3-valent P as a donor is transferred near +5-valent V, the orbital hybridization between V-3d and O-2p will lead to a suitable reduction in the band gap width of SrTiO3. The band edge alignment respect to water redox potentials proves that its band edges match well with the redox potentials of water. It was also found that P and V co-doping could reduce the complexation of photogenerated carriers and create a new optical absorption peak in the visible range. The calculated results imply that the P and V co-doping could improve the visible light photocatalytic activity of perovskite SrTiO3. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Theoretical calculations show that +3-valent P-doped SrTiO3 can improve the photocatalytic performance of SrTiO3 when co-doped with metal ions. The co-doping of Phosphorus and Vanadium in SrTiO3 system can enhance visible light photocatalytic activity by reducing carrier recombination and creating a new optical absorption peak in the visible range.