摘要：为了研究CeO₂对LaCoO₃结构及光催化性能的影响,采用溶胶-凝胶法结合真空干燥技术和后期热处理合成Ce与La物质的量比分别为0.1、0.3、0.5的CeO₂-LaCoO₃超细混合粉体;采用热重-差热分析、X射线衍射、X射线光电子能谱、红外光谱、比表面积和透射电子显微镜等手段对粒子的微观结构进行表征;以功率为10 W的紫外灯为光源,选用甲基橙的光催化降解反应考察超细粒子的光催化性能。结果表明:Ce的掺杂未对粉体的钙钛矿结构产生明显影响,粉体晶相由LaCoO₃钙钛矿相以及CeO₂混合而成;CeO₂相的存在明显提高了LaCoO₃的光催化性能,Ce与La物质的量比为0.3时粉体的光催化性能最好,甲基橙溶液最大降解率为92.5%。

关键词：CeO_2；LaCoO_3；溶胶-凝胶法；晶体结构；光催化降解

Abstract： To discuss the effect of CeO₂ on structure and photocatalytic performance of LaCoO₃， ultrafine mixed powders of CeO₂-LaCoO₃ with the amounts of substance ratio of Ce and La of 0.1， 0.3 and 0.5 were synthesized by the method of sol-gel combining with vacuum drying and heat treatment. The particles were characterized by the methods of TG - DTA， XRD， XPS， IR， specific surface area and TEM. The photocatalytic performance was evaluated under the degradation reaction of methyl orange taking an ultraviolet lamp with the power of 10 W as the light source. The results show that the adding of Ce has no obvious effect on perovskite structure of powders. The crystal phase of powders is composed of LaCoO₃ and CeO₂. The existing of CeO₂ phase enhances photocatalytic performance of particles. The powders with the amount of substance ratio of Ce and La of 0.3 show the best photocatalytic performance， and the degradation rate of methyl orange can reach 92.5%. 

Keywords: cerium dioxide； lanthanum cobaltate； sol-gel method； crystal structure； photocatalytic degradation