Anisotropic thermoelectric transport properties in polycrystalline SnSe2

• 作者: Caiyun Li Wenke He Dongyang Wang Li-Dong Zhao
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
• 页码范围: 541-549
• 页数: 9页
• 语种: 英文
• DOI: 10.1088/1674-1056/abeee1

摘要

It is reported that SnSe2 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 SnSe2 is improved through introducing SnSe phase and electron doping (Cl doped in Se sites).The anisotropic transport properties of SnSe2 are inves-tigated.A great reduction of the thermal conductivity is achieved in SnSe2 through introducing SnSe phase,which mainly results from the strong SnSe2-SnSe inter-phase scattering.Then the carrier concentration is optimized via Cl doping,lead-ing 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 compre-hensive consideration on the anisotropic thermoelectric transport properties,an enhanced figure of merit ZT is attained and reaches to ～ 0.6 at 773 K in SnSe2-2％ SnSe after 5％ Cl doping along the ||P direction,which is much higher than ～ 0.13 and ～ 0.09 obtained in SnSe2-2％ SnSe and pristine SnSe2 samples,respectively.