Group-IVA element-doped SrIn2O4 as potential materials for hydrogen production from water splitting with solar energy.

Abstract

Band gap engineering can efficiently improve the photocatalytic activity of semiconductors for hydrogen generation from water splitting. Herein, we present a comprehensive investigation on the geometrical structures, electronic, optical, and potential photocatalytic properties and charge carrier mobility of pristine and group-IVA element-doped SrIn2O4 using first-principles density functional theory with the meta-GGA+MBJ potential. The calculated formation energies are moderate, indicating that the synthesis of the doped structures is experimentally feasible. In addition, the energy band gaps of the group-IVA element-doped SrIn2O4 range from 1.67 to 3.07 eV, which satisfy the requirements for photocatalytic water splitting, except for that of the Si mono-doped structure. Based on the deformation potential theory, a high charge carrier mobility of 2093 cm2 V−1 s−1 is obtained for the pristine SrIn2O4 and those of the doped-structures are also large, although a decrease in the values of some are observed. The optical absorption coefficient of the doped structures in the near ultraviolet (UV) and visible light range significantly increases. Therefore, group-IVA element-doped SrIn2O4 are potential candidates as photocatalysts for hydrogen generation from water splitting driven by visible light.