Study of phase transformation dynamics, structural and optical properties of ferroelectric SrTiO3 ceramics

Abstract In this work, ferroelectrics of the SrTiO3 type were obtained using solid-phase synthesis method and subsequent thermal annealing. Using the X-ray diffraction method, the dynamics of phase transformations of the TiO2/Sr2Ti6O13/Sr3Ti2O7 → TiO2/Sr2Ti6O13/Sr3Ti2O7/SrTiO3 → SrTiO3/Ti3O5 type was established. According to the data obtained, it was found that thermal annealing in the range of 200–1100 °C allows obtaining both complex multiphase ceramics and SrTiO3 ceramics with a perovskite structure. As a result of determination of the optical properties, it was found that an increase in the structural ordering degree and the formation of a stable SrTiO3 phase, a broad induced absorption band appears in the region of 3.0–3.3 eV, with a maximum of 3.14 eV. During the determination of ferroelectric characteristics, it was found that the formation of a stable SrTiO3 phase in ceramics structure leads to a sharp increase in dielectric constant and a decrease in Curie-Weiss temperature from 125-130 °C to 105–110 °C.