金属アルコキシドからのBaTiO₃粒子の合成と評価

抄録

Barium titanate (BaTiO₃) powders were prepared by hydrolysis of Ba-Ti bimetallic alkoxides containing octyl groups. The as-prepared BaTiO₃ particles were amorphous in submicron size (-0.5μm). Crystalline BaTiO₃ particles were obtained on preheating at 393K in a flow of oxygen/water vapor mixed gas and successive heating at 673K in oxygen atmosphere. The introduction of water vapor suppressed the formation of BaCO₃, resulting in the formation of highly crystalline BaTiO₃. The microstructure of BaTiO₃ bodies sintered at 1573K exhibited grain sizes of 10-15 μm. They showed dielectric constant of about 2500 and the loss tangent of about 0.02 at the room temperature (1kHz).