SmCoO_3的固相合成及性质  

Solid-state Synthesis and Properties of SmCoO_3

作　　者：刘润茹[1] 许大鹏[1] 李霜[1] 吕喆[2] 薛燕峰[1] 王德涌[1] 苏文辉[1] 

机构地区：[1]吉林大学物理学院 [2]哈尔滨工业大学凝聚态科学与技术研究中心,哈尔滨150001

出　　处：《吉林大学学报（理学版）》2005年第5期658-661,共4页Journal of Jilin University:Science Edition

基　　金：国家自然科学基金(批准号:30370406)

摘　　要：以Sm2O3和Co2O3为原料,使用高温固相反应法合成SmCoO3正交钙钛矿化合物,采用X射线衍射、Raman谱、热膨胀仪和高温电导等测试技术对样品进行了结构和性能研究.结构分析表明,Sm2O3与Co2O3在1 353 K附近可以进行固态反应,形成单相性很好的SmCoO3正交钙钛矿相.高温电导测量显示单相SmCoO3随温度升高由绝缘体向半导体转变,Arrhenius图表明绝缘体—半导体转变点在470 K附近.单相SmCoO3的热膨胀系数在873 K以上为2.17×10-5K-1,和掺杂LaGaO3的相近,但明显大于SDC(Ce0.85Sm0.15O2)的热膨胀系数.The solid-state reaction method was used to prepare the perovskite oxide SmCoO3. The structure and properties of the samples have been investigated by XRD, Raman spectral techniques and DC measurements and so on. The XRD and Raman spectra show that the mixtures of Co2O3 and Sm2O3 can form a single phase perovskite oxide SmCoO3 by solid-state reaction around 1 353 K. The clearly observed band in the room temperature Raman spectra of single-phase SmCoO3 is at 140 - 175 cm^-1, which is assigned to the stretching of Sm--O and the winding of O--Sm--O. The single-phase SmCoO3 is an insulator below 600 K, and the conductivity is enhanced obviously with temperature increasing above 600 K. This may be explained by the fact that an insulator to semiconductor transition occurs around 470 K. The thermal expansion coefficient （2.17 × 10% -5 K^-1 ） of the single-phase SmCoO3 is approximately equal to that of doped LaGaO3, but bigger than that of SDC （Ce0.85Sm0.15O2 ） above 873 K.

关 键 词：SmCoO3 固相反应 阴极材料 结构表征 电导率 

分 类 号：O643.4[理学—物理化学]