The seed size effect on final size of BaTiO3 synthesize by hydrothermal reaction

Abstract

BaTiO3 has been extensively used in multilayer ceramic capacitor (MLCC) because of its outstanding dielectric properties. The advances in microelectronic packaging and communication technologies necessitate the ultra – high capacity of the MLCC. As the dielectric material layer of MLCC becomes thinner, the nano sized BaTiO3 powder, below 100 nm, are more essential to produce the ultra – high capacity of MLCC. It is also important that the nano – sized BaTiO3 powder has higher tetragonality contradictory to size effect. Our work contains the scope of the establishment of synthesis technique of the nano-sized BaTiO3 powder by hydrothermal route for the improved tetragonality, higher uniformity, and low dispersity of the nano powder. This work has targeted to investigate the conditions for synthesizing nano-sized tetragonal BaTiO3 powder with the specific characteristics of DSEM50 < 70 nm and c / a > 1.007. As a result, nano-sized BaTiO3 particles were synthesized by a hydrothermal method using Ba(OH)2ㆍH2O, Ti – butoxide as precursor materials, EtOH as a solvent and ammonia, amine and acid as surfactants. Synthesis conditions for the BaTiO3 nano powders of below 70 nm were established and the BaTiO3 has the tetragonality c / a about 1.0071. The synthesized BaTiO3 nanostructures are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).