The effect of Mg-doping on the structural and electronic properties of ZnTiO ₃ : a first-principles study and compared with experimental band gap of ZnTiO ₃

Abstract This paper shows a detailed analysis of the structural and electronic properties of pure zinc titanate (ZnTiO 3 ) and magnesium (Mg)-doped ZnTiO 3 (Zn 1−x Mg x TiO 3 , where x = 0.167, 0.333, 0.5, and 0.667) and compared with experimental band gap of ZnTiO 3 . We conducted the analysis using first-principles and density-functional-theory calculations using the Quantum Espresso package. The objective was to investigate the effect of Mg substitution on zinc titanate ZnTiO 3 . In the pure ZnTiO 3 system, calculations reveal an indirect electronic structure gap. At a doping level of 0.333, ZnTiO 3 with Mg impurities have an indirect electronic structure gap of 1.81 electron volts (eV). The investigation of structural and electronic characteristics indicates that x = 0.333 Mg doped ZnTiO 3 significantly reduce the electronic structure gap of ZnTiO 3 while maintaining the same kind of electronic structure gap, which is an indirect electronic structure gap. The density functional theory study shows that Mg substitution in ZnTiO 3 change their electronic structure and density of states and experimental band gap is nearly same as computational band structure gap which validates the exchange–correlation treatment and pseudopotentials employed for the band-structure calculation for this system.