Effects of Sn-deficiency on thermoelectric properties of polycrystalline Sn1-xSe compounds

• Published in: Current applied physics Vol. 17; no. 5; pp. 732 - 737
• Main Authors: Lee, Sang Tae, Kim, Min Ji, Lee, Gil-Geun, Kim, Sung Gyoo, Lee, Soonil, Seo, Won-Seon, Lim, Young Soo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2017; 한국물리학회
• Subjects: Polycrystal; SnSe; SnSe2; Thermoelectric; 물리학; SnSe2; Thermoelectric; ZT; SnSe; Polycrystal
• ISSN: 1567-1739; 1878-1675
• DOI: 10.1016/j.cap.2017.02.007

The effects of Sn-deficiency on the thermoelectric properties of polycrystalline Sn1-xSe (x = 0, 0.01, 0.02, and 0.04) compounds were investigated. The Sn-deficiency caused the formation of the SnSe2 secondary phase in the compounds, and the charge and thermal transport properties were affected significantly by the secondary phase. Although the Sn-deficient compounds exhibited higher thermal conductivities than stoichiometric compound due to its high thermal conductivity of SnSe2, significantly improved power factors led to the enhancement of ZT. The highest ZT of 0.61 at 848 K was achieved in Sn0.98Se compound, and detailed effects of SnSe2 on the enhancement were discussed. •The first study on the thermoelectric properties of Sn1-xSe compounds.•Significant role of SnSe2 secondary phase on the thermoelectric transport properties.•Enhancement of ZT by Sn-deficiency without intentional doping of foreign elements.