Deng, Ping-YuanPing-YuanDengWang, Kuang-KuoKuang-KuoWangDu, Jia-YuJia-YuDuHSIN-JAY WU2024-09-182024-09-182020https://www.scopus.com/record/display.uri?eid=2-s2.0-85090439648&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/721167論文編號: 2005479PbTe-based alloys have been widely used as mid-temperature thermoelectric (TE) materials since the 1960s. Years of endeavor spurred the tremendous advances in their TE performance. The breakthroughs for n-type PbTe have been somewhat less impressive, which limits the overall conversion efficiency of a PbTe-based TE device. In light of this obstacle, an n-type Ga-doped PbTe via an alternative thermodynamic route that relies on the equilibrium phase diagram and microstructural evolution is revisited. Herein, a plateau of zT = 1.2 is achieved in the best-performing Ga0.02Pb0.98Te in the temperature range of 550–673 K. Notably, an extremely high average zTave = 1.01 is obtained within 300 − 673 K. The addition of gallium optimizes the carrier concentration and boosts the power factor PF = S2ρ−1. Meanwhile, the κL of Ga-PbTe reveals a significantly decreasing tendency owing to the defect evolution that changes from dislocation loop to nano-precipitation with increasing Ga content. The pathway for both the κL reduction and defect evolution can be probed by an equilibrium phase diagram, which opens up a new avenue for locating high zT TE materials. © 2020 Wiley-VCH GmbHdislocationn-type PbTenano-precipitationthermal conductivitythermodynamic approaches[SDGs]SDG7journal article10.1002/adfm.2020054792-s2.0-85090439648