Preparation of Functional Gradient Material n-PbTe with Continuous Carrier Concentration

Functional gradient materials (FGMs) in thermoelectric materials can raise the maximal power output of the thermoelectric generator (TEG). We report an FGM of n-PbTe with continuous carrier concentration successfully prepared by a unidirectional solidification method. The continuous carrier concentration for n-PbTe was optimized by different dopants of PbI₂, Al and Zr and solidifying temperature. The effective maximum outputting power for continuous FGM PbTe is about 30% larger than that for jointed FGM PbTe.