Electrical and optical properties of SrTiO₃ nanopowders: Effect of different dopants Ba and Ag

Abstract

Using strontium–titanium salts precursor, nanopowders (STO-based-NPs) were successfully synthesized by controlled gel-combustion method. Citric and nitric acids in an optimum ratio were used as the fuel and oxidizer agents, respectively. After heat treatment at 850[Formula: see text]C, the crystalline structure of the products was investigated by X-ray diffraction. The effects of Ba and Ag dopants on particle size distribution were discussed by transmission electron microscopy (TEM). The optical and dielectric parameters such as energy band gap [Formula: see text], real and imaginary parts of refractive index, dielectric function and energy loss function of nanopowders have been investigated by UV–Vis and FTIR spectra. The band gap of SrTiO3 increased with increasing Ba, Ag and Ba–Ag. Different atomic radii of dopants are responsible for changing optical and dielectric parameters due to the altered orbital configuration of the lattice structure.