Anomalous enhancement of thermoelectric power factor by thermal management with resonant level effect. Issue 8 (28th January 2021)

• Record Type: Journal Article
• Authors: Sakane, Shunya; Ishibe, Takafumi; Mizuta, Kosei; Fujita, Takeshi; Kiyofuji, Yuga; Ohe, Jun-ichiro; Kobayashi, Eiichi; Nakamura, Yoshiaki
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 8(2021)
• Page Start: 4851
• Page End: 4857
• Publication Date: 2021-01-28
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0ta08683e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Thermoelectric power factor enhancement through thermal management with resonant level effect is experimentally demonstrated in SiGeAu composite system. Abstract : Obtaining high thermoelectric performance has been the biggest historical challenge for thermoelectric power generation. Here, we propose a methodology for thermoelectric power factor enhancement: thermal management with resonant level effect for simultaneous increase of electrical conductivity σ and Seebeck coefficient S . Au crystals and Au impurities are introduced into SiGe. Therein, (1) highly-conductive Au crystals increased σ . (2) Au impurities brought about resonant level effect and phonon scattering, resulting in enhanced S and lowered thermal conductivity κ of SiGe. (3) This κ distribution control brings the focus of temperature difference on SiGe parts with lowered κ, resulting in the availability of the enhanced S of SiGe parts as effective S of the entire nanocomposite. Consequently, we achieved the highest S 2 σ at room temperature among SiGe-related materials ever reported. Electronic structure calculation and measurement support the existence of resonant levels, which enhances S and lowers κ . These results provide a new route to thermoelectric performance enhancement.