有机溶剂中溶胶-凝胶法制备纳米钙钛矿型氧化物  

Preparation of Nanometer Perovskite-Type Oxides by Sol-Gel Method with Organic Solvent

作　　者：郭鹏[1] 邵光杰[1] 胡婕[1] 孙丽娟[1] 刘海彪[1] 郑礼明[1] 

机构地区：[1]燕山大学环境与化学工程学院,河北秦皇岛066004

出　　处：《中国稀土学报》2006年第z1期49-52,共4页Journal of the Chinese Society of Rare Earths

基　　金：河北省自然科学基金资助项目(B200400189)

摘　　要：以柠檬酸作配位剂,无水乙醇为溶剂,采用有机溶剂的溶胶-凝胶法合成了纳米钙钛矿型氧化物LaMnO3及La1-xSrxMnO3。用TG/DTA对金属羧酸盐凝胶的热分解历程进行了分析,用XRD分析了所得产物的相组成,以TEM观察了不同制备条件下的纳米粉体的颗粒尺寸及其形貌特征。结果表明,与水溶液相比,在有机溶剂中能够获得尺寸更小的纳米钙钛矿粉体。研究了溶液pH值和柠檬酸用量对La1-xSrxMnO3前驱体溶胶凝胶稳定性的影响。通过实验确定最佳的工艺条件为pH=8,柠檬酸添加量与金属离子总量的比值为2∶1。Perovskite-type oxides LaMnO3 and La1-xSrxMnO3 were synthesized by the organic solvent sol-gel method.The desired metal cations were chelated in a solution using citric acid as the chelating agents and ethanol absolute as solvent.The thermal decomposition of the metal carboxylate precursor gels was studied by TG/DTA and the products derived from calcinations of the gels were characterized by XRD and TEM.The results reveal that the nanometer perovskite-type powers with smaller particle size can be achieved with organic solvent.The effect of pH value and molar ratio of citric acid∶Nb cation on the formation of homogeneous La1-xSrxMnO3 precursor gels was also studied. The results show that the optimal pH value is 8,and the amount ratio of citric acid and Nb cation is 2∶1.

关 键 词：有机溶剂 钙钛石 溶胶-凝胶法 稀土 

分 类 号：TG146.4[一般工业技术—材料科学与工程] O611.61[金属学及工艺—金属材料]