First-Principles Calculations of the Structural, Electronic and Optical Properties of Yttrium-Doped SnO2

We use FP-LAPW method to study structural, electronic, and optical properties of the pure and Y-doped SnO₂. The results show that by Y doping of SnO₂ the band gaps are broadened, and still direct at Γ-point. For pure SnO₂ material, the obtained values of the direct band gap are 0.607 eV for GGA-PBE and 2.524 eV for GGATB-mBJ, respectively. This later is in good agreement with the experimental data and other theoretical results. The Fermi level shifts into the valence band and exhibits p-type semiconductor character owing mainly from the orbital 4d-Y. Additionally, the calculated optical properties reveal that all concentrations are characterized by low reflectivity and absorption via wavelength λ (nm) in the visible light and near-infrared (NIR) ranges, which leads to a redshift in the optical transparency.