Largely Optimized Thermoelectric Performance in (Ag, S) Coalloyed Cu 2 Te Thermoelectric Materials

作者：Yi Niu, P. Luo, Hailong Sun, Jie Song, Xinrui He, Chao Wang, Jing Jiang · 发表于：ACS Applied Materials & Interfaces · 年份：2025 · DOI：10.1021/acsami.5c14459 · 被引用次数：4 · 研究领域：Advanced Thermoelectric Materials and Devices、Advanced Thermodynamics and Statistical Mechanics、Innovation Diffusion and Forecasting

Cu 2 Te-based compounds are expected to exhibit superior thermoelectric performance compared to Cu 2 S and Cu 2 Se due to the larger atomic mass and more covalent bonding of Te atoms, such as chalcogenide selenide and chalcogenide lead. However, the currently reported figure of merit ( ZT ) for Cu 2 Te is still lower than that of Cu 2 S and Cu 2 Se. In this work, the thermoelectric transport properties are studied and optimized by two-step coalloying of Cu 2 Te-based materials. An improved average power factor of 7.21 μW cm –1 K –2 is obtained between room temperature and 773 K because of the largely optimized carrier concentration and Seebeck coefficient. Additionally, the total thermal conductivity decreases to 0.55 W m –1 K –1 for Ag 0.7 Cu 1.3 Te 0.94 S 0.06 W m –1 K –1 at room temperature, and the lowest thermal conductivity of 0.49 W m –1 K –1 is obtained in Ag 0.7 Cu 1.3 Te 0.92 S 0.08 at 523 K because of the tuned carrier concentration and increased entropy. Combined with the simultaneous optimization of electrical transport properties and thermal transport properties, (Ag, S) coalloyed Cu 2 Te shows a maximum ZT of 1.4 at 773 K, which is 460% higher than that of Cu 2 Te at the corresponding temperature.