Synergistic Performance of Thermoelectric and Mechanical in Nanotwinned High‐Entropy Semiconductors AgMnGePbSbTe <sub>5</sub>
Zheng Ma, Yubo Luo, Jinfeng Dong, Yukun Liu, Dan Zhang, Wang Li, Chengjun Li, Yingchao Wei, Qinghui Jiang, Xin Li, Huabing Yin, Vinayak P. Dravid, Qiang Zhang, Shaoping Chen, Qingyu Yan, Junyou Yang, Mercouri G. Kanatzidis
Abstract
Abstract Introducing nanotwins in thermoelectric materials represents a promising approach to achieving such a synergistic combination of thermoelectric properties and mechanical properties. By increasing configurational entropy, a sharply reduced stacking fault energy in a new nanotwinned high‐entropy semiconductor AgMnGePbSbTe 5 is reached. Dense coherent nanotwin boundaries in this system provide an efficient phonon scattering barrier, leading to a high figure of merit ZT of ≈2.46 at 750 K and a high average ZT of ≈1.54 (300—823 K) with the presence of Ag 2 Te nanoprecipitate in the sample. More importantly, owing to the dislocation pinning caused by coherent nanotwin boundaries and the chemical short‐range disorder caused by the high configurational entropy effect, AgMnGePbSbTe 5 also exhibits robust mechanical properties, with flexural strength of 82 MPa and Vickers hardness of 210 H V .