This project deals with the control of the physical and chemical characteristics of BaTiO3 powder by developing a synthesis route which is simple and economical. This research should ultimately lead to the first synthesis technique which produces a narrow size distribution BaTiO3 powder with submicron, unagglomerated particles and a 1:1 Ba:Ti ratio at a synthesis temperature as low as 100oC. Synthesis of such powder may also lead to great processing advances in the production of BaTiO3 electrical ceramics. The synthesis route for this powder is envisioned to require three consecutive stages: 1) synthesis of monodisperse hydrous titania 2) hydrothermal reaction of a sterically stabilized dispersion of monodisperse hydrous titania in a strongly alkaline aqueous solution of Ba(OH)2 3) acetic acid rinsing to remove all residual Ba(OH)2. Completion of stage one will be accomplished using methods established by previous workers. Successful completion of stage two will rely on simultaneously maintaining BaTiO3 formation and colloidal stability throughout the hydrothermal reaction. Study of stage two is possible with in situ and intermittent measurements using conventional powder and solution characterization to monitor the effect of the chemical processing variables on the progress of the hydrothermal reaction. Identification of the critical processing variables which control the powder characteristics will enable achievement of the ultimate objective and a better fundamental understanding of the process.
