Homo‐Crystalline Interfaces for Durable Thermoelectric Generation
Kaikai Pang, Ruoyu Wang, Zejian Dong, Qiang Zhang, Ruijie Li, Ruyuan Li, Li Kong, Yao Wang, Jiehua Wu, Guo‐Qiang Liu, Xianhu Sun, Jun JiangABSTRACT
Enhancing average dimensionless figure of merit ( ZT ) through segmentation is central to thermoelectric energy conversion, yet practical application is hindered by the kinetic and electrical instability of conventional soldered hetero‐interfaces. Herein, we introduce a seamless partitioning (SP) approach that creates compositionally graded, homo‐crystalline interfaces within Bi‐Sb‐Te through a one‐step sintering process, eliminating foreign interlayers. The yielded coherent and semi‐coherent interfaces with minimal misfit strongly suppress interdiffusion and defect mobility, establishing an intrinsically stable interfacial configuration with a thermally robust contact resistivity and bulk‐like mechanical integrity, based on which SP‐based modules achieve a conversion efficiency up to 7.6% at a temperature difference of 250 K, outperforming state‐of‐the‐art Bi 2 Te 3 ‐ and Mg 3 (Bi,Sb) 2 ‐based modules and retaining stable performance after 100 h of thermal endurance. This interface‐intrinsic design links atomic configuration, kinetic stability, and module‐level reliability, offering a general blueprint for high‐performance thermoelectric.