Effect of sintering temperature on structural and electrical properties of BiFeO₃ multiferroics

Abstract

Polycrystalline samples of BiFeO₃ are synthesized at low temperature using sol-gel technique. From the XRD analysis it is seen that crystallite size increases and the strain in the crystallites decreases with increasing sintering temperature. As the crystallite size increases with increasing temperature the lattice parameter (<i style="">a_R</i>) decreases. SEM micrographs show that the samples are homogeneous. It is also confirmed from the SEM micrographs that the grain size increases with increasing sintering temperature. Analyzing the SEM micrographs it can be concluded that the particle size follows the Gaussian distribution. Ferroelectric to paraelectric transition temperature (<i style="">T</i>_c) is detected by DTA analysis, which shows that the Curie temperature of pure BiFeO₃ is 814°C which is very close to the ideal value (827°C) found by dielectric measurement.