|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Alloys and Compounds for Thermoelectric and Solar Cell Applications IX
||Defect Evolution Enabling Low Thermal Conductivity and High Thermoelectric Performance for n-type PbTe
||Ping-Yuan Deng, Kuang-Kuo Wang, Jia-Yu Du, Hsin-Jay Wu
|On-Site Speaker (Planned)
The PbTe-based alloys have been extensively utilized as mid-temperature thermoelectric materials since the 1960s. During the adventure on chasing high-performance PbTe via doping, it comes to realize that the breakthroughs for n-type PbTe are less impressive, which limits the overall conversion efficiency of a PbTe-based TE device. In light of this obstacle, the Gallium is incorporated into the PbTe, which tunes the carrier concentration by introducing the additional impurity traps within the bandgap. Also, the κL reveals a significantly decreasing tendency, accompanying with the defect evolution that changes from a dislocation loop to nano-precipitation with increasing Ga content. The footmark for the κL reduction can be probed by an equilibrium phase diagram, which opens up a new avenue for locating the high-zT TE materials. The synergy approach of carrier optimization and defect engineering rejuvenate the well-established TE materials and boost their performance even beyond existing records.