The large band gap of SrTiO3 is disadvantageous for photocatalytic applications. We therefore study cation codoping to modify the size of the band gap and extend the absorption to visible light. We identify efficient codoping schemes that guarantee charge compensation to avoid creation of localized states. Using the Heyd–Scuseria–Ernzerhof hybrid functional, we analyze the crystal and electronic structures as well as the optical properties. It is found that (Nb/Ta, Ga/In) codoping does not reduce the band gap, in contrast to (Mo/W, Zn/Cd) codoping. The position of the conduction band edge after (Mo, Cd) codoping impedes a high photocatalytic efficiency, whereas (Mo/W, Zn) and (W, Cd) codoping are found to be favorable.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: M. M. Fadlallah thanks A. A. Maarouf and U. Eckern for fruitful discussions. This work was supported by NWO Exacte Wetenschappen (Physical Sciences) for the use of supercomputing facilities, with financial support from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (Netherlands Organization for Scientific Research, NWO). The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST).