Studies on electrical and dielectric properties of co-precipitated Aurivillius phase Ca1−xBaxBi2Nb2O9 ceramics

Polycrystalline samples of lead free Ca1−xBaxBi2Nb2O9 ceramics has been synthesized by simple chemical co-precipitation method. Single phase layered perovskite structure was confirmed by X-ray diffraction with average crystallite size in the range of 46-57 nm. Randomly oriented grains with inhomogeneous morphology was observed by scanning electron microscopy. Study of dielectric constant and corresponding tangent loss was carried out in the frequency range of 1 Hz to 5 MHz at room temperature. Ca1−xBaxBi2Nb2O9 shows maximum value of dielectric constant of 535 at 1 Hz. The highest polarization of 0.026 μC/cm2 was obtained at an applied electric field of 10 kV/cm using PE loop measurement.