Studies on Thermoelectric Properties of n-type Polycrystalline SnSe[subscript 1-x]S[subscript x] by Iodine Doping

• Main Authors: Zhang, Qian (Author), Chere, Eyob Kebede (Author), Sun, Jingying (Author), Cao, Feng (Author), Dahal, Keshab (Author), Chen, Shuo (Author), Chen, Gang (Contributor), Ren, Zhifeng (Author)
• Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor)
• Format: Article
• Language: English
• Published: Wiley Blackwell, 2015-11-10T18:34:19Z.
• Subjects: Article
• Online Access: Get fulltext

Iodine-doped n-type SnSe polycrystalline by melting and hot pressing is prepared. The prepared material is anisotropic with a peak ZT of ≈0.8 at about 773 K measured along the hot pressing direction. This is the first report on thermoelectric properties of n-type Sn chalcogenide alloys. With increasing content of iodine, the carrier concentration changed from 2.3 × 10[superscript 17] cm[superscript −3] (p-type) to 5.0 × 10[superscript 15] cm[superscript −3] (n-type) then to 2.0 × 10[superscript 17] cm[superscript −3] (n-type). The decent ZT is mainly attributed to the intrinsically low thermal conductivity due to the high anharmonicity of the chemical bonds like those in p-type SnSe. By alloying with 10 at% SnS, even lower thermal conductivity and an enhanced Seebeck coefficient were achieved, leading to an increased ZT of ≈1.0 at about 773 K measured also along the hot pressing direction.
United States. Dept. of Energy. Office of Science (Solid-State Solar-Thermal Energy Conversion Center Award DE-SC0001299)