Studies of structural, dielectric and impedance spectroscopy of Sr/Zr modified BiFeO3 ceramics

Bismuth ferrite (BiFeO3) is the most commonly used multiferroics for multifunctional applications. The polycrystalline samples of co-doped (Sr/Zr) bismuth ferrite (BiFeO3) of a general chemical composition, Bi1-xSrx)(Fe1xZrx)O3, x = 0.05, 0.1, 0.15, 0.20, were prepared using a standard solid-state reaction method. The basic structural data of the above synthesized electro-ceramics were obtained by X-ray diffraction data and pattern. The surface morphology of the samples was recorded at room temperature by a scanning electron microscope. The scanning electron microscope images show the uniform distribution of grains throughout the surface of the samples. Studies of dielectric and impedance properties of the samples at varying frequency (1 kHz-1000 kHz) and temperature (250C-300 degrees C) have provided many important information about the materials. The existence of ferroelectricity in the materials was studied by the electric field dependent polarization. The contributions of both grains and grain boundaries towards the total resistance and capacitive behavior of the compounds have been studied by analyzing the frequency and temperature dependence of impedance data.. Study of frequencytemperature dependence of ac-conductivity has provided the information on the type of conduction mechanism. The J-E characteristics of the samples provide the Ohmic behavior with slope closer to 1.