First-principles studies on electronic structure and optical properties of anatase TiO₂ doped with Sn

The relationship between electronic structure and some optical properties of Sn doped titanium dioxide (TiO2) was investigated by first principles calculation based on density function theory (DFT). The influence of dopant concentration or distance on the electronic structure and optical properties were studied. The gradual increase of Sn doping makes the absorption edge of TiO2 red-shift and enhances the optical performance in the visible light region. Furthermore, experiments have detected that the bandgap of TiO2 becomes bigger as the distance between two doped Sn atoms increases. The findings will provide certain theoretical basis for the present field of energy research.