Crystallographic design for half-Heuslers with low lattice thermal conductivity. (July 2022)

• Record Type: Journal Article
• Authors: Ren, Wuyang; Shi, Xin; Wang, Zhiming; Ren, Zhifeng
• Is Part Of: Materials today physics. Volume 25(2022)
• Publication Date: 2022-07
• Subjects: Materials science -- Periodicals; Physics -- Periodicals; Electronic journals; 530.41
• DOI: 10.1016/j.mtphys.2022.100704
• Languages: English
• ISSNs: 2542-5293

Abstract

Abstract: Exploring novel materials with intrinsically low lattice thermal conductivity ( κ L ) is an effective way to advance thermoelectrics. Half-Heuslers (HHs) are known for their large thermoelectric power factor, but they suffer from intrinsically high κ L . Their rich chemical compositions and unique atomic arrangements make possible novel HH exploration through crystallographic design, and various low- κ L HHs have thus been reported. Here these emerging HHs are categorized according to the origin of the intrinsically low κ L, i.e., heavy-element-containing HHs with low sound velocity, defective non-18-electron HHs with intrinsic point defects, and quaternary double HHs with a complex structure. In addition to their intrinsically low κ L, the decent thermoelectric performance and other fascinating properties observed in these HHs could attract increasing attention and may play an important role in HH research. Graphical abstract: Image 1 Highlights: Rational crystallographic design contributes to discovery of intrinsically low- κ L -half-Heuslers. Designing ternary 18-electron half-Heuslers with heavy elements is an effective way to reduce phonon velocity. Vacancies introduced to stabilize the structure of 19-electron half-Heuslers will result in a shortened mean free path. Intrinsically low κ L and vast number of possible stable compounds make quaternary half-Heuslers attractive.