新材料「熱電永久磁石」で世界最高電力密度の横型熱電発電に成功 ～磁石を用いた革新的省エネ・創エネ技術へと前進～

2025-03-18 物質・材料研究機構,東京大学,名古屋大学,科学技術振興機構​

​＜関連情報＞

• https://www.nims.go.jp/press/2025/03/202503180.html
• https://www.jst.go.jp/pr/announce/20250318/pdf/20250318.pdf
• https://pubs.rsc.org/en/content/articlelanding/2025/ee/d4ee04845h

過去最高の横方向熱電発電を実現する多機能複合磁石 Multifunctional composite magnet realizing record-high transverse thermoelectric generation

Fuyuki Ando,Takamasa Hirai, Abdulkareem Alasli, Hossein Sepehri-Amin,Yutaka Iwasaki,Hosei Nagano and  Ken-ichi Uchida
Energy & Environmental Science  Published:18 Mar 2025
DOI:https://doi.org/10.1039/D4EE04845H

Abstract

Permanent magnets are used in various products and essential for human society. If omnipresent permanent magnets could directly convert heat into electricity, they would lead to innovative energy harvesting and thermal management technologies. However, achieving such “multifunctionality” has been difficult due to poor thermoelectric performance of conventional magnets. In this work, we develop a multifunctional composite magnet (MCM) that enables giant transverse thermoelectric conversion while possessing permanent magnet features. MCM comprising alternately and obliquely stacked SmCo₅/Bi_0.2Sb_1.8Te₃ multilayers exhibits an excellent transverse thermoelectric figure of merit z_xyT of 0.20 at room temperature owing to the optimized anisotropic structure and extremely low interfacial electrical and thermal resistivities between the SmCo₅ and Bi_0.2Sb_1.8Te₃ layers. The MCM-based thermopile module generates a maximum of 204 mW at a temperature difference of 152 K, whose power density normalized by the heat transfer area and temperature gradient is not only record-high among transverse thermoelectric modules but also comparable to those of commercial thermoelectric modules utilizing the Seebeck effect. The multifunctionality of our MCM provides unprecedented opportunities for energy harvesting and thermal management everywhere permanent magnets are currently used.