Theoretical investigation of structural, electronic and optical properties of Sc-doped SnO2

Abstract

In this study, the structural, and optoelectronic properties of ScxSn1-xO2 alloys with (x = 0, 0.0416, 0.0625 and 0.125) are investigated using the first principle method with a full-potential linearized augmented plane wave (FP-LAPW) as implemented in WIEN2k code, which is based on density functional theory (DFT). We used the generalized gradient approximation parameterized of Perdew-Burke and Ernzerhof (PBE-GGA) to calculate the structural properties, while the electronic and optical properties were determined using the Tran–Blahamodified Becke-Johnson (TB-mBJ) potential functional which gives improved band gaps compared to PBE-GGA.

The results reveal that by Sc-doping SnO2 the band gaps broaden and remain direct at Γ. When substituting Sc-impurities, the Fermi level is displaced into the valence band due to the 3d-Sc orbital producing a p-type semiconductor. The optical response shows low absorption, reflectivity and the blue shifting of the optical transmittance in Sc-doped SnO2 due to an increase in of the band gap, according to the Burstein-Moss effect. Our results reveal that Sc-doped SnO2 could be useful for transparent conducting applications.