Low leakage current density and improved dielectric behavior of BiFexO3 nano-ceramics

BiFexO3 (x = 0.8, 1.0, 1.2) sample were prepared using citrate precursor method sintered at 600 degrees C. The X-ray diffraction (XRD) patterns confirmed the rhombohedral structure of BiFexO3 samples. The average crystallite size was found to about 50 nm. Higher value of tensile strain was observed for the samples with the excess and deficiency of iron contents in Williamson- Hall plots. Surface morphology of these isostructural materials were studied using Field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM). Average particle size estimated from TEM for the sample BiFe1.2O3 is found to be about 55 nm. FTIR studies reported two strong peaks at 444 cm(-1) and 544 cm(-1) supporting the formation of pervoskite structure. The value of leakage current density of BiFe1.2O3 is reduced by two orders of magnitude (similar to 1.34 x 10(-10) A/cm(2)) which may be ascribed to the suppression of oxygen and Bi vacancies. Dielectric measurements of these samples were greatly affected by the excess and deficiency of Fe content in BFO. BiFe1.2O3 samples were found to have higher value of dielectric constant similar to 315 at 1 kHz. (C) 2020 Elsevier B.V. All rights reserved.