Influence of samarium and iron substitution on structural and electrical properties of barium zirconate titanate solid solutions

Abstract

Solid solutions of (x)SmFeO3-(1-x)Ba(Zr0.05Ti0.95)O3: x = 0, 0.21, 0.22 and 0.23 were synthesized by the solid-state reaction route. Le-Bail analysis of the X-ray diffraction data and Raman spectra revealed the presence of the tetragonal phase (P4mm space group 99). The remnant polarization (Pr) was ~4.08 µC/cm2 and 1.04 µC/cm2 for x= 0 and x= 0.21, respectively, while lossy loops were observed for x≥ 0.22. Canting of the antiferromagnetic spins and ferromagnetic exchange mechanism was responsible for the ferromagnetic feature in the samples. An increase in remnant magnetization (Mr) was observed with increases in x. The Nyquist plots revealed the existence of grain and grain boundaries in the overall impedance. Separation of the normalized plots of impedance (Z˝) and modulus (M˝) spectra indicated localized motion of the charge carriers in the sample. The Maxwell–Wagner model fits very well in the low-frequency region (105 Hz). The ac conductivity obeyed the Universal Jonscher’s Power law. The variations in the exponent n suggest that the conduction mechanism conforms to the small polaron hopping mechanism.