Study of Effect of y substitution on structural, dielectric, impedance and magnetic properties of Bismuth Ferrite

Abstract

Yttrium substituted Bismuth Ferrite of a composition, Bi(Fe0.95Y0.05)O3 (abbreviated as BFYO5) has been synthesized through a conventional mixed oxide route. The orthorhombic crystal structure and a pure-phase formation of the polycrystalline material was verified through X-ray diffraction pattern. The composition of its constituent elements and their concentration ratio were confirmed by using energy dispersive X-ray spectroscopy technique. Scherrer's equation was used to estimate the average crystallite size of the examined sample specimen and found to be 39 nm. Analysis of the BFYO5 compound's surface morphology was conducted using field emission scanning electron microscope, which clearly shows a densely packed specimen with a homogeneous distribution of various grain dimensions. The interrelationship between frequency and temperature in dielectric, impedance and conductivity parameters with the structure of a sample has also been reported. The impedance spectroscopy analysis shows the nature of negative temperature coefficient of resistance, grain and its boundary effect on the resistive and capacitive features and the presence of non-Debye type of electrical relaxation process in the studied material. The analysis of polarization versus electric field shows the improvement in the value of remnant polarization comparing with the parent compound bismuth ferrite. The substantial enhancement in the magnetization value of the prepared material was also confirmed by its magnetic hysteresis loop study. Based on an important enhancement in the electrical properties, remnant polarization and its magnetic properties, BFYO5 material could be considered as a promising candidate for some of the advance device applications.