PRODUCTION OF LACOO3 HAVING PEROVSKITE STRUCTURE

摘要

PURPOSE:To obtain a thin film of perovskite LaCoO3 and a powder thereof having a uniform particle size which can be sintered at low temp. by subjecting a mixture liquid of salts of La and Co in a specified ratio to electrolysis at a constant potential or a constant current in a specified range. CONSTITUTION:Electrolysis is performed in a mixture liquid of salts of La and Co [La/Co =1000 (molar ratio)] as an electrolytic soln. at a constant voltage of 0.7-1.3V (Ag/AgCl as the referential potential) or a constant current of =0.5mA/cm2. When the potential ranges 0.7-0.95V, a single phase of LaCoO3 can be obtd., while in the range of 0.95-1.3V, a mixture phase of LaCoO3 and Co3O4 can be obtd. However, when the voltage is out of these ranges or the current exceeds 0.5mA/cm2, no material having LaCoO3 composition can be obtd. It is preferable to control the electrolytic liquid at =50 deg.C and pH 3-7. By controlling the time for electrolysis, a film or powder of LaCoO3-base multiple oxide can be produced, which is then sintered at =500 deg.C in the presence of oxygen.