Structure, surface morphology and optical properties of BaTiO3 powders prepared by wet chemical method

Abstract

Barium titanate powders were synthesized by the wet chemical method using the starting materials barium chloride (BaCl₂), titanium dioxide (TiO₂) and oxalic acid with different calcinations temperature. The XRD pattern of BaTiO₃ calcined at 500 ˚C showed cubic phase whereas BaTiO₃ samples calcined at 700 ˚C and above showed tetragonal phase. The crystallite size, strain and dislocation density were calculated from the XRD spectrum. It was found that crystallite size increases with increase of calcination temperature. EDS spectrum was used to identify the composition of the material. Absorption co-efficient (α), extinction co-efficient (K) and optical band gap were estimated from the optical reflectance spectrum. The band gap of the powder was found to be decreasing with the increase of calcination temperature. Nanoparticles of both spherical and rod like in shape were clearly observed in the SEM.