BaTiO3 perovskite for optoelectronics application: A DFT study

Abstract

BaTiO3 perovskite material is an attractive material for optoelectronics applications. Here, we discuss the results of our investigations using density functional theory(DFT)into the BaTiO3 structure. The computations were performed utilizing Generalized Gradient Approximation (GGA) and Local Density Approximation (LDA) through SIESTA code. In the current study, we have calculated the electronic properties such as energy band structure, density of states (DOS)/eV and optical properties of the BaTiO3 perovskite material. The band structure of this material was estimated using the Spin Orbital Coupling (SOC) effect. The band gap value for the BaTiO3 perovskite material produced by GGA is 1.54 eV and LDA is 1.67 eV, which is quite comparable with previously reported work. The calculated DOS and PDOS for this perovskite materials show that the states of Ti-3d and O-2p has a significant effect on the electronic properties. The static dielectric constant, reflectivity R(ω), absorption coefficient α(ω) and refractive index n(ω) have also been estimated in terms of optical characteristics. The results obtained on the optical properties such as the low reflectivity rate and high absorption of the incident photon energy range in GGA is 2–4 eV and LDA is 2–5 eV. This energy range suggests that BaTiO3 in perovskite solar cells has a good optical response to absorbingsolar wavelengths.