Design of efficient thermoelectric generators

Thermoelectricity, which enables direct conversion between heat and electricity, undergoes impressive developments in recent decades, and is particularly promising for recovering low-grade heat of <600 K [1,2]. Currently, only Bi2Te3-based thermoelectric devices are commercialized [3]. However, the scarcity of tellurium (Te)(Fig. 1a) is the main concern. This leads to numerous recent efforts on the development of efficient nonBi2Te3 thermoelectrics as potential alternatives, and successful examples (Fig. 1b) include Mg3Sb2-alloys [2,3] and MgAgSb[1,2].In addition to materials’ thermoelectric performance, the