Promising doped and co-doped CeO2 and TiO2 oxides for optoelectronic applications: First principles approach

Wide-gap oxides are promising materials for optoelectronic applications due to their exceptional optical, electronic, and structural properties. This paper explores the impact of doping and co-doping on the structural, electronic, magnetic, and optical properties of CeO2 and TiO2 using a first-principles approach based on the full potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory (DFT). The results show that doping and co-doping lead to a significant change in the lattice parameters, which is of paramount importance as it affects the fundamental properties of the compounds. The optimized structural parameters authenticate the stability of the ferromagnetic phases, and the formation energies justify the stability conditions of the compounds. Furthermore, a half-metallic character with an indirect band gap (spin-up) and semiconductor features is achieved for doping and co-doping models based on CeO2 and TiO2, respectively. There is no significant difference between single doping and co-doping in terms of total magnetic moment values since both single doping and co-doping compounds contribute a total magnetic moment of 2μB each. In addition, after the doping process, many optical parameters, including the absorption coefficient and dielectric constants, become much better, resulting in amplified absorption peaks in the visible and UV areas. These findings suggest that compounds exhibit interesting features for spintronic and optoelectronic technologies. © 2024 Elsevier GmbH