CORRELATION BETWEEN STRUCTURE AND ELECTRICAL CHARACTERISTICS IN SAMARIUM DOPED BARIUM TITANATE SYSTEMS

Abstract

Conventional solid-state method was used to prepare powders of barium titanate (BT) doped with different concentration of Sm. Influence of Sm addition on the structure modification, grain growth inhibition and microstructure development was studied. Dielectric properties of doped samples were significantly modified. With doping, a diffuse kind of ferro-para phase transition was induced, phase transition positions were moved and dielectric permittivity values were lowered. On the other hand, Sm doping affected the decrease of dielectric losses. The impedance complex plane plots showed a one single semicircular arc, indicating grain contribution as a main effect on the total conduction of the doped materials. On the other hand, different electro-active regions in the modulus plane plots were distinguish. The comparison between impedance and modulus scaling behavior presented the localized movement of charge carriers. P-E hysteresis loops have shown the dilution of ferroelectric properties with Sm doping.