High dielectric constant of (1-x)(Na0.5Bi0.5)TiO3-xBaTiO3 prepared by the hydrothermal method

Abstract

In this study, hydrothermal synthesis conditions for the formation of (1-x (Na0.5Bi0.5)TiO3-xBaTiO3 (x=0; 0.03; 0.05; 0.06; 0.07; 0.08 and 0.1) compounds were investigated. The process parameters such as the alkaline conditions and heating treatment (temperature, time) as well the influence of the (Na, Bi)/Ba ratio were investigated in detail. The as-prepared NBT powders were characterized by X-ray powder diffraction, scanning electron microscope (SEM) and dielectric measurements. Taking into account NBT behavior draws consideration to phenomena of the ion ordering, coexistence of various phase regions in a crystal lattice, phase transition diffusion and a considerably new phenomenon: the existence of a very high dielectric constant at low frequency. Our result presents a simple preparation route for low-cost and high-purity.