Structural and electrical properties of four-layers Aurivillius phase BaBi3.5Nd0.5Ti4O15 ceramics

A new compound of barium bismuth neodymium titanate BaBi3.5Nd0.5Ti4O15 was synthesized using the traditional solid-state reaction method. X-ray diffraction analysis confirmed the compound to be a layered tetragonal structure and Raman spectrum indicated that Nd ions occupy the A site. The plate-like morphology with average grain size about 2-4 μm was observed by a scanning electron microscope (SEM). A precision impedance analyzer was used to measure the dielectric properties and impedance spectroscopy of the ceramics. The results show that the temperature of dielectric constant maximum (Tm), the room temperature dielectric constant (εr) and loss (tan δ) at 100 kHz are 287° C, 326 and 0.017, respectively. The modified Curie-Weiss law was used to describe the relaxor behavior of the ceramics which was attributed to the A site cationic disorder. The remnant polarization (2Pr) of the sample was observed to be 1.27 μC/cm2 at room temperature.