REACTION SEQUENCES IN THE SYSTEMS TI(OIPR)4+BA(CH3COO)2 AND TIO2+BA(CH3COO)2

The reaction sequences during BaTiO3 formation from the systems Ti(OiPr)4 + Ba(CH3COO)2 and TiO2 + Ba(CH3COO)2 are studied, using a sol-gel method for the former system and solid-state reaction for the latter. The sol-gel system exhibits greater reactivity, forming BaTiO3 at temperatures as low as 500-degrees-C; also, the formation of the intermediate Ba2TiO4 occurs to a much lesser extent than in the case of solid-state reaction. An explanation of the structure and behaviour of the gel system is proposed from X-ray diffraction, infrared and thermogravimetric examinations. Under appropriate treatments, both systems yield microstructures with fine and homogeneous grain size; however, the sol-gel method facilitates a complete reaction at temperatures appreciably lower than those needed with the solid-state reaction system.