Structural, morphological, electrical and ferroelectric properties of lead free Ba_0.985Sr_0.015Zr_0.10Ti_0.90O₃ ceramics

The strontium and zirconium co-doped barium titanate compound have been chosen for analysis to explore Ba_0.985Sr_0.015Zr_0.10Ti_0.90O₃ (BSZT) ceramic for energy storage applications. The selected compound was prepared using the standard solid state reaction technique and sintered at various sintering temperatures, T_s, 1200, 1250 and 1300°C. Rietveld refinement was used on the X-ray diffraction pattern to confirm the crystal structure of the BSZT samples and each sample indicates the tetragonal phase with the P4mm space group. Morphological analysis of the BSZT samples showed that higher T_s can attain a dense microstructure. Temperature and frequency dependence dielectric properties were studied. The relationship between the microstructural-properties (i.e. grain and grain boundary) and the relaxation process in BSZT was studied with detailed explanation of both the complex impedance and the modulus spectroscopy. A non-Debye type relaxation process was observed in BSZT. The ferroelectric behaviors of the sample were explored by recording the polarization versus electric field hysteresis loops at room temperature.