Electrical response in poled (Bi0.5Na0.5)0.935Ba0.065TiO3 ceramics

Abstract

A ferroelectric material (Bi0.5Na0.5)0.935Ba0.065TiO3 (BNBT) with a perovskite structure was poled and characterized by electrical impedance spectroscopy as a function of temperature, X-ray diffraction, and Rietveld refinement. The ac conductivity showed a low-frequency dispersion, supporting the idea of heterogeneous potential wells favored by Bi3þ, Naþ, and Ba2þ on the A site of the perovskite type of structure. The activation energies for ac conduction depended on the studied frequency. The permittivity and electrical modulus showed a distribution of the relaxation time associated with the delay in the orientation of the dipoles and an important contribution to the short-range conductivity.