Preparation of Highly Dispersed BaTiO₃ Nanoparticles by Surfactant with High Density of Hydrophilic Group

Abstract

We discussed the action mechanism of a microbial-derived surfactant, which had low molecular weight and high density in hydrophilic carboxyl groups, on preparation of highly dispersed barium titanate particles with several 10 nm in suspension by sol-gel method. By addition of this surfactant during synthesis process of particles, barium titanate nano-particles with high dispersion stability in suspension were prepared. To analyze the action mechanism, the adsorption behavior on the surface of particles and the surface interaction between particles were characterized. The action mechanism estimated that this surfactant formed the complex with Ba²⁺ ion in barium hydroxide aqueous solution before mixing with titanium tetraisopropoxide and hydrolysis reaction was taken place with Ba²⁺ in complex and the surfactant was added to the surface of barium titanate nano particles.