Impact of rare earth (RE³⁺ = La³⁺, Sm³⁺) substitution in the A site perovskite on the structural, and electrical properties of Ba(Zr_0.9Ti_0.1)O₃ ceramics

Abstract

Undoped Ba(Zr_0.9Ti_0.1)O₃ and rare-earth-doped (Ba_1-<i>x</i> RE_2<i>x</i>/3)(Zr_0.9Ti_0.1)O₃ (RE³⁺ = La³⁺, Sm³⁺) perovskite compounds were synthesized by the conventional solid-state reaction route. Both solubility of rare earth in Ba(Zr_0.9Ti_0.1)O₃ and formation of perovskite structure with the <i>Pm</i>3̄<i>m</i> space group were verified by the Rietveld method using X-ray diffraction data. SEM micrographs of all ceramics revealed high densification, low porosity, and even homogeneous grain distribution of various dimensions over the total surface. The frequency-dependent electrical properties were analyzed by complex impedance spectroscopy. Different types of studies such as the Nyquist plot, real and imaginary part of impedance, conductivity, modulus formalism, and charge carriers activation energy were used to explain the microstructure-electrical property relationships.