|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Alloys and Compounds for Thermoelectric and Solar Cell Applications X
||Realizing High Thermoelectric Figure of Merit of Co-doped GeTe Alloy via Phase Diagram Engineering
||Szu-Chien Wu, Yi-Fen Tsai, Hsin-Jay Wu
|On-Site Speaker (Planned)
GeTe-based alloys have shown promising thermoelectric performance in recent years. Phase diagram engineering has been proposed as an effective strategy to optimize the thermoelectric properties through manipulating microstructure. Based on the Sn-Ge-Te phase diagram, a structural transition zone exists between the rhombohedral- and cubic-(SnTe, GeTe) solid solution. In order to maintain rhombohedral structure, lightly doping is adopted. Lightly Sn-doped GeTe solid solution shows the decent electrical conductivity σ and power factor PF = S2σ. However, Sn substitution scarcely decreases the carrier concentration, and thermal conductivity remains a high value at high temperature. Therefore, slightly Sb and Bi co-doping are introduced to optimize the carrier concentration and thermal conductivity. The large mass fluctuation caused by co-doping significantly reduces the lattice thermal conductivity. The lightly co-doped rhombohedral-GeTe alloys show promising thermoelectric performance.