Abstract: Well dispersed tetragonal BaTiO3 superfine powders were prepared by hydrothermal method under milder conditions. Influences of reaction conditions，such as amount-of-substance ratio of Ba2+ to Ti4+，reaction temperature，time，and alkalinity of the reaction system，on hydrothermal synthesis of tetragonal BaTiO3 nano-powder were investigated systematically and the optimized preparation conditions were obtained.Tetragonal BaTiO3 powders with particle size of 80~140 nm could be prepared when the reactants with amount-of-substance ratio of Ba2+ to Ti4+ of 2.0∶1，reacted at 180 ℃ for 72 h under strong alkali condition.Chemical analysis result showed the amount-of-substance ratio of barium to titanium of the sample was at 0.995~1.005. Tetragonal BaTiO3 powders with particle size of 100~200 nm were successfully prepared with the industrial materials at the rotating condition in 500 L high pressure reactor in industrial scale experiment.

Key words: barium titanate, tetragonal, nano-powder, hydrothermal synthesis, industrial experiment