First-principles study of effects of Al doping on electronic structures and optical properties of SnO2

Abstract

The electronic structures and optical properties of tin dioxide (SnO2) with different Al-doping concentrations (x = 0, 0·0185 and 0·0417) are investigated using the first-principles calculation of plane wave ultra-soft pseudo-potential technology based on the density functional theory under the local-density approximation. The results show that the Fermi level of Al-doped SnO2 goes into the valence band, indicating that Al-doped SnO2 is a typical p-type semiconductor. Moreover, with the increase in Al-doping concentrations, the band gap of SnO2 is broadened and the blueshift of the absorption spectrum becomes significant, which are in good agreement with the experiment results. In addition, the low reflectivity (<15%) in the visible light range is obtained.