Oxygen-vacancy-induced structural transition and enhanced magnetism in Sc, Fe-codoped SrTiO3: A theoretical study

[Display omitted] •Electronic transition of (Fe + Sc)-doped SrTiO3 (STO) with and without oxygen vacancy were studied by first-principles calculations.•The magnetism of (Fe + Sc)-STO could be significantly improved by introducing oxygen vacancy.•Spin magnetic moment was almost linearly increased due to the strong hybridization between Fe dopant and the nearest O atoms.•(Fe + Sc)-codoping and oxygen vacancies aimed at performance enhancement in STO-based dilute magnetic semiconductor. The spin-polarized electronic structure and magnetism of (Fe + Sc)-doped SrTiO3 (STO) with and without oxygen vacancy are investigated through first principles calculations. The computations show that codoping with Fe and Sc leads to the formation of spin-splitting half-metallic electronic band structure and induces a total magnetic moment of about 3.58 μB/supercell. The magnetism is formed by the strong hybridization between Fe 3d and O 2p states. A transition from half-metallic to semiconductor is observed with further introducing an oxygen vacancy. The magnetic moment of (Fe + Sc)-STO with oxygen vacancy is enhanced to 5 μB/supercell due to vacancy-induced structure distortion and increased magnetization.