摘要： A systematic investigation based on spin-polarized DFT + U has been carried out to study the electronic structure of charge compensated (Os, 2N)-codoped SrTiO3 as compared with that of pure SrTiO3, Os-doped SrTiO3, N-doped SrTiO3, and charge non-compensated (Os, N)-codoped SrTiO3. The calculated band gap of pure SrTiO3 is improved to 3.22 eV using GGA + U method by choosing appropriate U values, which is in good agreement with the experimental value (3.25 eV). Although charge non-compensated co-doping with (Os, N) significantly reduces the photoabsorption energy by introducing localized in-gap impurity states of Os-5d, N-2p, and O-2p, unfortunately, the presence of these states may hinder charge carrier mobility. The calculated results show that the charge compensated co-doping with one Os and two N leads to the complete passivation of the mid gap Os-5d and O-2p impurity states, thus the positions of the band edges are extended to satisfy the criteria for overall water splitting under visible-light. The present predictions demonstrate that the charge compensated (Os, 2N)-codoped SrTiO3 can be a desirable effective photocatalyst for highly active visible-light-induced hydrogen production from water splitting due to the enhanced visible-light activity as well as decreased electron–hole recombination rate.