First-principles calculations of electronic and optical properties of A and B site substituted BaTiO3

Abstract

In order to better understand the doping process at A site and B site, we have researched the X (Sr2+, Zn2+, Nd3+, Ni2+, Zr4+, Hf4+) doping of barium titanate (BaTiO3) by using the CASTEP. This work computed the distinct optical, structural, and electrical characteristics before and after doping and analyzed them in depth. After doping, the addition of Sr, Zn and Nd causes the low energy level and conduction band of the system to shift to the direction of low energy, and narrows the band gap. While after the B-site ion replaces Ti, the width and intensity of the conduction band state density also widen and increase. What's more, after doping, the cubic phase rises to the tetragonal phase, increasing the quality of BaTiO3. The optical spectra have dramatically different energy characteristics, making doped BaTiO3 promising for applications in a variety of optical and optoelectronic installations.