ABSTRACT
Si-rich compounds in the Mn-Si binary system are called “higher manganese silicides” (HMSs) and have been known as potential thermoelectric (TE) materials for more than 50 years [1-3]. Although the gure of merit, ZT, of the material is less than unity, HMSs have recently attracted renewed interest as they consist of naturally abundant and lesstoxic elements and are chemically and thermally stable in the atmosphere. By adopting rst-principles calculations to design alloys and cutting-edge techniques to modify microstructures, the TE performance has recently been gradually improved. Now, it is no longer a dream that the TE performance exceeds ZT > 1. In this chapter, we will review key milestones in the long history of HMS research of the stoichiometry, crystal structure, TE properties, thermal expansion, and so on. We will also give some insights on how to obtain HMS-based materials with superior TE performance.
