Half-Heusler alloys as emerging high power density thermoelectric cooling materials

Hangtian Zhu; Wenjie Li; Amin Nozariasbmarz; Na Liu; Yu Zhang; Shashank Priya; Bed Poudel

doi:10.1038/s41467-023-38446-0

Half-Heusler alloys as emerging high power density thermoelectric cooling materials

Nat Commun. 2023 Jun 6;14(1):3300. doi: 10.1038/s41467-023-38446-0.

Authors

Hangtian Zhu^#^{1

2}, Wenjie Li^#³, Amin Nozariasbmarz⁴, Na Liu⁴, Yu Zhang⁴, Shashank Priya⁵, Bed Poudel⁶

Affiliations

¹ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA. htzhu@iphy.ac.cn.
² Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China. htzhu@iphy.ac.cn.
³ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA. wzl175@psu.edu.
⁴ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA.
⁵ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA. sup103@psu.edu.
⁶ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA. bup346@psu.edu.

^# Contributed equally.

Abstract

To achieve optimal thermoelectric performance, it is crucial to manipulate the scattering processes within materials to decouple the transport of phonons and electrons. In half-Heusler (hH) compounds, selective defect reduction can significantly improve performance due to the weak electron-acoustic phonon interaction. This study utilized Sb-pressure controlled annealing process to modulate the microstructure and point defects of Nb_0.55Ta_0.40Ti_0.05FeSb compound, resulting in a 100% increase in carrier mobility and a maximum power factor of 78 µW cm^-1 K^-2, approaching the theoretical prediction for NbFeSb single crystal. This approach yielded the highest average zT of ~0.86 among hH in the temperature range of 300-873 K. The use of this material led to a 210% enhancement in cooling power density compared to Bi₂Te₃-based devices and a conversion efficiency of 12%. These results demonstrate a promising strategy for optimizing hH materials for near-room-temperature thermoelectric applications.

Abstract

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