钙钛矿型氧化物Ln_(0.5)Sr_(0.5)CoO_3的制备与电输运性能  

Preparation and Electrical Transport Properties of Perovskite Oxide Ln_(0.5)Sr_(0.5)CoO_3

作　　者：朱志强[1] 丁铁柱[1] 赵倩[1] 张利文[1] 王强[1] 

机构地区：[1]内蒙古大学理工学院物理系,内蒙古呼和浩特010021

出　　处：《中国稀土学报》2006年第4期438-441,共4页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金资助项目(10464001);内蒙古教育厅重大项目(NJ03119);内蒙古大学513人才计划资助项目

摘　　要：采用固相反应法合成钙钛矿氧化物材料Ln0.5Sr0.5CoO3(Ln=La,Pr,Nd,Sm,Eu)的超细粉体,研究了不同稀土元素掺杂时的晶体结构和电输运性能,分析了该钙钛矿体系结构的形成过程。实验表明,当烧结温度达到1200℃时,通过固相反应法可以形成稳定的单一的钙钛矿相。样品电导率在700℃附近出现最大值,低温段的导电行为符合小极化子导电机制,La0.5Sr0.5CoO3材料的电导率在中温范围内最大,适合作为中温固体燃料电池的阴极材料。The superfine powders of Ln0.5 Sr0.5 CoO3 （Ln= La, Pr, Nd, Sm, Eu）were obtained by solid state reactions. The crystal structure and electrical transport properties of samples doped with different rare earth elements as well as the forming process of the Perovskite structure were studied. The result shows that when the temperature reaches 1200℃, the samples will become a steady and unitary Perovskite phase by solid state reactions. The conductive behavior at low temperature is consistent with small polaron mechanism （i. e., localized electronic carriers having a thermally activated mobility）. However, the maximum of conductivity appears at about 700℃, and the conductivity of La0.5Sr0.5CoO3 is the biggest in the intermediate-temperature （600 - 850℃ ）, so it is fit for cathode material of intermediate-temperature solid oxide fuel cells.

关 键 词：Ln0.5Sr0.5CoO3 钙钛矿型氧化物 电输运 平均晶粒度 稀土 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TM262.05[一般工业技术—材料科学与工程]