La填充Ni置换n型Skutterudite热电材料的制备及性能  

Preparation and Thermoelectric Properties of La Filled and Ni Substituted n-type Skutterudite Thermoelectric Materials

作　　者：鲍思前[1] 杨君友[1] 朱文[1] 李守林[1] 樊希安[1] 段兴凯[1] 

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室

出　　处：《材料科学与工程学报》2008年第3期328-330,399,共4页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(50401008)

摘　　要：起始原料使用La、Co、Ni和Sb元素粉末,采用机械合金化(MA)和热压烧结(HP)的方法制备了名义成分为LaxNi0.2Co3.8Sb12(x=0.1,0.3,0.5,0.7)n型填充Skutterudite化合物热电材料,研究了不同La含量对MA-HP成型后的相组成及热电性能的影响。研究结果表明,机械合金化10h后的粉末,在650℃热压2h后可得到单相Skutterudite结构化合物;随着La填充分数的增加,晶格常数增大;通过向Skutterudite结构的空隙中填充稀土La原子,能大幅度降低热导率;热电性能研究表明,La0.5Ni0.2Co3.8Sb12在750K左右能得到最大的ZT值0.33。Starting from element La, Ni, Co and Sb powders, nominal LaxNi0.2Co3.Sb12（x=0.1, 0.3, 0.5, 0.7） ntype filled Skutterudite was prepared by mechanical alloying （MA） and subsequent hot pressing （HP）. The effect of the La filling fraction on phase formation and thermoelectric properties was studied in this paper. It was found that single phase Skutterudite could be obtained when the powders milled for 10h were hot pressed at 650℃ for 2h and the lattice parameters increase with increasing the La filling fraction. The thermal conductivity was greatly decreased by filling rear-earth element La into the voids of Skutterudite structure. As a result, the La0.5 Ni0. 2Co3.8 Sb12 Skutterudite exhibits a maximum figure of merit of 0.33 at about 750 K.

关 键 词：热电材料 填充Skutterudite 机械合金化 热压 

分 类 号：TN304.2[电子电信—物理电子学] TF124[冶金工程—粉末冶金]