Dielectric properties of A-site Mn-doped bismuth sodium titanate perovskite: (Bi0·5Na0.5)0.9Mn0·1TiO3

Abstract We synthesized A-site Mn-doped Bi0·5Na0·5TiO3 polycrystalline ceramic ((Bi0·5Na0.5)0.9Mn0·1TiO3 ceramic (BNMT10)) via solid-state reaction route and investigated the structural and temperature-dependent dielectric properties. The dielectric properties of the synthesized samples are explained using the brick-layer model. The relaxation time and corresponding activation energies were obtained through the Arrhenius mechanism by using the imaginary impedance and modulus results. Analysis of the activation energy and other dielectric results suggests that the electric conduction in our BNMT10 sample is due to single and doubly charged oxygen ion vacancy-defects at low and high temperatures, respectively. The grains and grain boundaries contribute to the inherent defect-based conduction mechanism and the dielectric behavior. The electric modulus spectroscopy results discerned the non-Debye type relaxation processes that these processes consist of the localized and long-range relaxation processes. Our results demonstrate that the dielectric behavior of Bi0·5Na0·5TiO3 ceramics can be enhanced through Mn-doping at the A-site.