High figure-of-merit in the heavy-fermion UN 2 system for radioisotope thermoelectric applications
Year: 2020
Type: article
Abstract: The design of uranium-based thermoelectric (TE) materials presents a novel and intriguing strategy for directly converting nuclear heat into electrical power. Using high-level first-principles approach combined with accurate solution of Boltzmann transport equation, we demonstrate that a giant n-type power factor of 13.8 mW m −1 K −2 and a peak ZT value of 2.2 can be realized in the heavy-fermion UN 2 compound at 700 K. Such promising TE performance arises from the large degeneracy ( N v = 14) of heavy conduction band coupled with weak electron–phonon interactions, which is in principle governed by the strong Coulomb correlation among the partially filled U-5 f electrons in the face-centered cubic structure. Collectively, our theoretical work suggests that the energetic UN 2 could serve as both excellent heat source and efficient power convertor, which also uncovers an underexplored area for TE research.
Institutions: Wuhan University, China Academy of Engineering Physics
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W3051142314