Sol-gel synthesis and structure of La2O3–CoO–SiO2 powders

Abstract

LaCoO3 powders are studied because they exhibit interesting electrical, magnetic and catalytic properties. In this paper, new synthesized La2O3-CoO-SiO2 powders with different quantity of silica were prepared via solgel method in aqua media, starting from metal nitrates with different chelating agents. The relation between the reaction in solution, crystallization pathway and morphology were discussed. In LaCoO3-SiO2 powders, depending on the content of SiO2 and the treatment temperature (700–1100°C), different crystalline phases (LaCoO3, Co2SiO4 and La9.31(SiO4)6O2) were observed with the crystallite sizes ranging from 50 to 100 nm. It was proved that chemical composition and nature of used additives has influence on the phase formation and structure of obtained nanomaterials.

Keywords

• Sol-gel synthesis
• La2O3-CoO-SiO2
• Powders