Thermoelectric materials strengthened by defect engineering can also suffer from the compromise of plasticity, and in turn results in negative effect on the processability, reliability and durability of thermoelectric devices. Here, we introduce nano-twinned CuAgSe secondary phase to achieve simultaneously increased compressive strength and plasticity of the β-Ag₂Se pellets without obviously sacrificing the thermoelectric performance, as evidenced by our thermoelectric measurements. Our pellet shows a maximum compressive strength of 96 MPa, which is ∼104% higher than that of pristine Ag₂Se, ascribed to the impeded crack propagation by the CuAgSe secondary phase. An extraordinary deformation value of ∼19% is observed at the maximum compressive strength, which is attributed to the intrinsically large plastic deformation of the Ag₂Se matrix, the deformable nano-twinned CuAgSe secondary as well as the interaction between the Ag₂Se matrix and the CuAgSe secondary phase. This work indicates that introducing nano-twinned secondary phase in thermoelectric materials is a promising strategy for developing high-performance thermoelectric materials with high strength and plasticity.

通过缺陷工程强化的热电材料也会受到可塑性的影响，进而对热电器件的可加工性、可靠​​性和耐用性产生负面影响。在这里，我们引入了纳米孪晶 CuAgSe 第二相，以在不明显牺牲热电性能的情况下同时提高 β-Ag ₂ Se 颗粒的压缩强度和塑性，我们的热电测量证明了这一点。我们的球团的最大压缩强度为 96 MPa，比原始 Ag _{2 的}压缩强度高约 104%Se，归因于 CuAgSe 第二相阻碍裂纹扩展。在最大抗压强度下观察到约 19% 的异常变形值，这归因于 Ag ₂ Se 基体固有的大塑性变形、可变形的纳米孪晶 CuAgSe 次生以及 Ag ₂ Se 基体之间的相互作用和 CuAgSe 第二相。这项工作表明，在热电材料中引入纳米孪晶二次相是开发具有高强度和可塑性的高性能热电材料的一个有前景的策略。