Frequency and temperature dependent electrical characteristics of NBT based ceramics prepared by Sol-gel method

Abstract

The preparation of the individual powders for the sodium bismuth titanate-based composites 0.90NBT + 0.10ST and 0.90NBT + 0.10CT (where NBT = Na0.5Bi0.5TiO3, ST = SrTiO3, and CT = CaTiO3) takes place through a solid state reaction process. Where individual powders are prepared with Sol gel chemical route. Studies using XRD and SEM confirm the formation of composites. Microstructure of the composites shows large grains. Temperature-dependent studies of dielectric and PE loops are conducted. The relative density, grain size, and ST concentration influenced the polarization properties of the specimens. The phase transition in NBT is associated with changes in alignment of dipoles into micropolar regions. For NBCT composite, the ferroelectric and polarization properties are degenerated. Activation energy of the composites was calculated using dielectric parameters.