Structural and dielectric properties of Sr substituted BaTi_0.8Zr_0.2O₃ perovskite synthesized via solid state reaction route

Perovskite type Ba_1−xSr_xZr_0.2Ti_0.8O₃ (with x = 0.0, 0.1, 0.2 and 0.3) ceramics have been synthesized through conventional two-step solid-state reaction method. The structural characterization was done using an X-ray diffraction study. All the compositions reveal a single-phase cubic structure. The dielectric measurements were taken at various temperatures (100 to 300 K) and various frequencies (1 to 500 kHz) for all the prepared compositions. This study reveals that the Ba_1−xSr_xTi_0.8Zr_0.2O₃ (with x = 0.0, 0.1, 0.2 and 0.3) composition does not transform from normal ferroelectric to relaxor ferroelectric. The diffusivity enhances with increment in Sr concentration in the present composition range. It is observed that with enhancement in Sr content, the transition temperature decreases for all the studied compositions. The decrease in transition temperature may occur due to introducing a smaller ionic radius of Sr²⁺ at the site of a larger ionic radius of Ba²⁺. The morphological properties of all the samples are analyzed using scanning electron microscopy images.