Preparation of Spherical, Solid Barium Titanate Particles with Uniform Composition at High Precursor Concentration by Spray Pyrolysis

Hydrolysis-assisted spray pyrolysis (HASP) using dimethyl oxalate as hydrolyte was found to be applicable to precipitation of solid, spherical BaTiO₃ powder with uniform composition when the stock solution concentration was high (>1.0 M ). Solid, dense powder with uniform composition was successfully obtained because barium titanium oxalate was prepared from partial hydrolysis of dimethyl oxalate and coprecipitation of oxalate with barium and titanium during the hydrolysis–precipitation process, and then the oxalate particles became seeds in the following process. The sintered sample from the as-prepared BaTiO₃ powder led to a higher dielectric constant and lower loss.