Optimization of the average figure-of-merit zT in medium-entropy GeTe-based materials via entropy engineering

Liu，Xusheng1,2,3; Wang，Keli4; Li，Peng2; Tang，Qiqi1,2,3; Huang，Zhenlong1,2; Lin，Yuan1; Wang，Wu3; Jiang，Binbin1,2; He，Jiaqing3

2024-07-01

10.1016/j.jmat.2024.02.014

Journal of Materiomics   影响因子和分区

2352-8478

2352-8486

Entropy engineering has emerged as an effective strategy for improving the figure-of-merit zT by decelerating the phonon transport while maintaining good electrical transport properties of thermoelectric materials. Herein, a high average zT of 1.54 and a maximum zT of 2.1 are achieved in the mid-entropy GeTe constructed by Ag, Sb, and Pb alloying. At room temperature, the mid-entropy GeTe tends to be a cubic structure. And the power factor is improved from 7.7 μW·cm·K to 16.2 μW·cm·K due to the large increase in effective mass and the optimized carrier concentration. The increasing disorder created by heavy and off-centering Ag, Sb, and Pb atoms induces strong mass/strain fluctuations and phonon scattering to decelerate the phonon transport in GeTe. A low lattice thermal conductivity is obtained in the medium-entropy GeTe-based material. Moreover, a GeTe-based thermoelectric cooler is fabricated with the cooling temperature difference of 66.6 K with the hot end fixed at 363 K. This work reveals the effectiveness of entropy engineering in improving the average zT in GeTe and shows potential application of GeTe as a thermoelectric cooler.

Entropy engineering Germanium telluride Thermoelectric Thermoelectric cooler

SCI

英语

其他

2-s2.0-85190822664

Scopus

1.School of Materials and Energy,University of Electronic Science and Technology of China,Chengdu,610054,China
2.Shenzhen Institute for Advanced Study,University of Electronic Science and Technology of China,Shenzhen,518110,China
3.Shenzhen Key Laboratory of Thermoelectric Materials,Department of Physics,Southern University of Science and Technology,Shenzhen,518055,China
4.Institute of Atomic and Molecular Physics,Sichuan University,Chengdu,610065,China

Liu，Xusheng,Wang，Keli,Li，Peng,et al. Optimization of the average figure-of-merit zT in medium-entropy GeTe-based materials via entropy engineering[J]. Journal of Materiomics,2024,10(4):956-963.

Liu，Xusheng.,Wang，Keli.,Li，Peng.,Tang，Qiqi.,Huang，Zhenlong.,...&He，Jiaqing.(2024).Optimization of the average figure-of-merit zT in medium-entropy GeTe-based materials via entropy engineering.Journal of Materiomics,10(4),956-963.

Liu，Xusheng,et al."Optimization of the average figure-of-merit zT in medium-entropy GeTe-based materials via entropy engineering".Journal of Materiomics 10.4(2024):956-963.