Investigation des propriétés électroniques et optiques du Ti0.875Mn0.125O2 via DFT

Abstract

In this work, an ab initio analysis was conducted to investigate the structural, electronic, and optical properties of pure titanium dioxide (TiO2) and manganese (Mn)-doped TiO2. The main objective was to assess the effect of doping on the optical properties of TiO2 rutile. This study relied on the full-potential linearized augmented plane wave (FP-LAPW) method implemented in the Wien2k code within the framework of density functional theory (DFT). The generalized gradient approximation using the Perdew-Burke-Erenterhof (GGA-PBE) parameterization, along with the Tran-Blaha modified Becke-Johnson (TB-mBJ) approach, was employed to account for exchange and correlation effects. The obtained results revealed that doping with manganese (Mn) at a 12.5% concentration induces structural modifications in titanium dioxide (TiO2) and leads to the formation of 3d-Mn impurity energy levels located above the valence band maximum and below the conduction band minimum. This modification results in a reduction of the bandgap width of TiO2 rutile, enhancing its optical absorption capabilities in the visible spectrum. Consequently, this can potentially increase its photocatalytic activity