High seebeck coefficient and low thermal conductivity in Bi and In co-doped GeTe thermoelectric material

• DOI: 10.1016/j.jmrt.2021.11.065
• Publication Date: 2021-11-19T23:16:16Z
• Authors: Hyerin Jeong; Samuel Kimani Kihoi; Hyunji Kim; Ho Seong Lee
• Keywords: Figure of Merit

Pure GeTe shows inferior thermoelectric performance due to the large carrier concentration caused by intrinsic high of Ge vacancies. In this study, we report improved Bi and co-doped based material where a figure merit, ZT ∼ 1.7 at 623 K was realized through synergetic effect tuning concentration, resonant states, suppression thermal conduction. doping induces states in density near Fermi energy level. sharply reduces lattice conductivity formation extensive solid solution point defects. Moreover, co-doping decreases phase transformation temperature widen better cubic low temperatures. addition, microstructural characterization showed herringbone structures, high-density domain boundaries, twinning. These, together with defects, lead significantly reduced conductivity.