Ytterbium Silicide (YbSi2): A Promising Thermoelectric Material with a High Power Factor at Room Temperature (Phys. Status Solidi RRL 2/2018). Issue 2 (5th February 2018)

• Record Type: Journal Article
• Authors: Tanusilp, Sora‐at; Ohishi, Yuji; Muta, Hiroaki; Yamanaka, Shinsuke; Nishide, Akinori; Hayakawa, Jun; Kurosaki, Ken
• Is Part Of: Physica status solidi. Volume 12:Issue 2(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-02-05
• Subjects: Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201870308
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : The so‐called power factor S 2 σ (with S the Seebeck coefficient and σ the electrical conductivity) determines the power generation performance of thermoelectric (TE) devices. Since S and σ have a trade‐off relationship as a function of carrier concentration, it has been difficult to enhance S 2 σ . Metal silicide‐based TE materials have attracted attention in the past two decades, because they are less toxic than conventional TE materials (such as Bi2 Te3 and PbTe), involve low production cost and show high chemical stability. The study by Ken Kurosaki and co‐workers (see article no.1700372 ) reveals that YbSi2 can be a good candidate of TE materials working near room temperature: Metallic YbSi2 has a specific layered structure and mixed valence state of Yb 2+ and Yb 3+, where Yb 2+ is the major ionic component at low temperature, and the amount of Yb 3+ increases with increasing temperature. This temperature‐dependent valence fluctuation would increase S with keeping high σ, which enables to enhance the power factor of YbSi2 to 2.2 mW m −1 K −2 which is comparable to that of Bi2 Te3 in the wide temperature range from room temperature to 523 K.