Thermoelectric properties of In-substituted Ge-based clathrates prepared by HPHT  

作　　者：Binwu Liu Hongan Ma Dexuan Huo Haiqiang Liu Baomin Liu Jiaxiang Chen Xiaopeng Jia 

机构地区：[1]National Key Lab of Superhard Materials,Jilin University,Changchun 130012,China [2]Institute of Materials Physics,Hangzhou Dianzi University,Hangzhou 310018,China

出　　处：《Journal of Materiomics》2018年第1期68-74,共7页无机材料学学报（英文）

基　　金：This workwas financially supported by National Natural Science Foundation of China(51171070);the Project of Jilin Science and Technology Development Plan(20170101045JC).

摘　　要：Bulk materials Ba_(8)Ga_(16)In_(x)Ge_(30-x)(x=0.5,1.0,1.5)were prepared by High-Pressure and High-Temperature(HPHT)method and the crystal structure has been confirmed by X-ray diffraction and cell refinement.The actual In composition was much lower than the starting composition,and lattice constants increased with the increase of substitution.As the temperature increased,the Seebeck coefficient and electrical resistivity increased first and then decreased,while the thermal conductivity was the opposite,which leads to significant enhancement on thermoelectric properties of the clathrates.The substitution of indium elements decreased the seebeck coefficient and electrical resistivity,and also changed the microstructure of the compounds.A minimum thermal conductivity of 0.84Wm^(-1)1K^(-1)was obtained,and a good ZT value of 0.52 was achieved.The grain boundaries and lattice defects generated by high pressure can effectively scatter phonons of different frequencies,which reduce the lattice thermal conductivity.

关 键 词：CLATHRATES HPHT Synthesis Thermoelectric properties 

分 类 号：TG1[金属学及工艺—金属学]