Résumé:
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
