RESEARCH ARTICLE

Robust mechanical properties of Ag₂Se_1–xTe_x thermoelectric materials

¹ State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
² Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
³ School of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, China
⁴ Wuzhen Laboratory, Tongxiang 314500, China
⁵ State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China

^* Corresponding authors (emails: tianran_wei@sjtu.edu.cn (Tian-Ran Wei); zpan@sjtu.edu.cn (Zhenyu Pan); xshi@mail.sic.ac.cn (Xun Shi))

Received: 4 February 2025
Revised: 15 April 2025
Accepted: 18 April 2025

Abstract

High mechanical robustness is essential to the material’s processibility for the applications in flexible and miniaturized electronics. As state-of-the-art room-temperature thermoelectric materials, Ag₂Se_1–xTe_x alloys exhibit superior thermoelectric transport properties but their mechanical properties remain largely unexplored. Herein, we systematically investigate the mechanical and thermoelectric properties of a series of Ag₂Se_1–xTe_x materials. Among them, Ag₂Se_0.9Te_0.1 shows robust mechanical properties including a large compression strain of (26.7 ± 4.5)%, a high compression strength of (279.2 ± 49) MPa, and an excellent fracture toughness of (4.5 ± 0.6) MPa m^1/2. These robust mechanical properties are ascribed to the dense dislocations as well as possible sub-grain rotations. Combined with the excellent thermoelectric figure of merit, zT of 0.78 at 300 K and 1.1 at 380 K, the Ag₂Se_1–xTe_x alloys are promising candidates for robust and efficient thermoelectric applications near room temperature.