Anisotropic thermoelectric transport properties in polycrystalline SnSe_(2)  

作　　者：Caiyun Li Wenke He Dongyang Wang Li-Dong Zhao 李彩云;何文科;王东洋;赵立东(School of Materials Science and Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]School of Materials Science and Engineering,Beihang University,Beijing 100191,China

出　　处：《Chinese Physics B》2021年第6期476-483,共8页中国物理B（英文版）

基　　金：supported by the Beijing Natural Science Foundation,China (Grant No. JQ18004);the National Key Research and Development Program of China(Grant Nos. 2018YFA0702100 and 2018YFB0703600);the National Natural Science Foundation of China (Grant No. 51772012);Shenzhen Peacock Plan Team (Grant No. KQTD2016022619565991);111 Project (Grant No. B17002);supported by the National Postdoctoral Program for Innovative Talents,China (Grant No. BX20200028);the high performance computing (HPC) resources at Beihang University;the support from the National Science Fund for Distinguished Young Scholars (Grant No. 51925101)。

摘　　要：It is reported that SnSe_(2) consisting of the same elements as SnSe, is a new promising thermoelectric material with advantageous layered structure. In this work, the thermoelectric performance of polycrystalline SnSe_(2) is improved through introducing SnSe phase and electron doping(Cl doped in Se sites). The anisotropic transport properties of SnSe_(2) are investigated. A great reduction of the thermal conductivity is achieved in SnSe_(2) through introducing SnSe phase, which mainly results from the strong SnSe_(2)–SnSe inter-phase scattering. Then the carrier concentration is optimized via Cl doping, leading to a great enhancement of the electrical transport properties, thus an extraordinary power factor of ^5.12 μW·cm^(-1)·K^(-2) is achieved along the direction parallel to the spark plasma sintering(SPS) pressure direction( P). Through the comprehensive consideration on the anisotropic thermoelectric transport properties, an enhanced figure of merit ZT is attained and reaches to ^ 0.6 at 773 K in SnSe_(2)-2% SnSe after 5% Cl doping along the P direction, which is much higher than ^ 0.13 and ^ 0.09 obtained in SnSe_(2)-2% SnSe and pristine SnSe_(2) samples, respectively.

关 键 词：THERMOELECTRIC SnSe_(2) anisotropic structure Cl-doping 

分 类 号：TB34[一般工业技术—材料科学与工程]