Research Progress of Half-Heusler Thermoelectric Materials and Application of Band Convergence Strategy

In this paper, we reviewed the research progress of half-Heusler (HH) thermoelectric (TE) materials, including traditional HH thermoelectric materials with 18 valence electrons in the crystal structure, as well as new HH thermoelectric materials. We briefly introduced several strategies to improve the TE performance of HHs, and focus on the band convergence strategy applied in TE property optimization. According to the existing research insufficiency, we proposed several aspects that need careful attention in TE material research in the future, such as the thermoelectric experimental research of HHs with valence electrons unequal to 18, the variation of band structure with alloying and temperature, and the establishment of a multiple band transport model which suitable for HH thermoelectric materials.