Synthesis and Characterization of Nano-Barium Titanate Prepared by Hydrothermal Process

Capacitors are the most convenient and economical devices for storage of electrical energy. Performance of a capacitor is primarily governed by solid-state characteristics of its dielectric material and the explicit value of the dielectric constant. Titanate ceramics such as Barium Titanate are popular capacitor dielectric materials because of their high dielectric constant and ferroelectric properties. In recent years, extensive research work has been done on Barium Titanate for multilayer ceramic capacitor application. Barium Titanate has been synthesized from high energy ball-milling process and sol-gel process or a thermo-chemical process. However, because of contamination from the grinding media, relatively wide particle size distribution and abnormal grain growth during the sintering, other novel synthesis processes have been developed. Nano-technology based hydrothermal synthesis is one such new process. In this paper, an effort has been made to synthesize nanocrystalline Barium Titanate through hydrothermal process. Characterization of the synthesized Barium Titanate is carried out by using X-ray diffraction for crystalline structure, scanning electron microscopy for microstructure and electron dispersive spectroscopy for chemical composition. Electric properties such as dielectric constant, dielectric dissipation factor and electrical resistivity have been measured. It has been observed that dielectric constant of about 4000 and dielectric dissipation factor of below 0.3 are obtained over a wide range of frequencies. The crystallite size of the optimized material is less than 50 nm.