Cu based ternary compounds have received intensive attentions as thermoelectric materials but their carrier mobility and thermal stability are subject to native Cu vacancy. In this work, the synergistic improvement in thermoelectric performance and stability in CuInTe is presented, facilitated by local chemical bond enhancement. Heavy dose Mg doping on In site can successfully suppress the formation of Cu vacancy in CuInTe and its thermal stability is significantly improved. As a result, In comparison to alternative dopants, Mg doping demonstrates a notable capacity for reinforcing the lattice structure through the inhibition of copper vacancies, thereby yielding a considerable enhancement in mobility by 20 %∼50 %, and the value of CuInMgTe exceeds 1.2 at 873 K. By further alloying with Ga on In site, the thermal conductivity is greatly reduced and more surprisingly the thermal stability is continuously enhanced. Notably, in Cu(InGa)MgTe, a peak value of 1.72 at 973 K is achieved, while in Cu(InGa)MgTe, an average value of 0.82 is attained. This study offers valuable insights into optimizing the thermoelectric performance and thermal stability of Cu-based ternary compounds through effective doping and defect regulation, providing guidance for future research in this field.

中文翻译：

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通过大剂量Mg掺杂实现CuInTe2的高热电性能和热稳定性


铜基三元化合物作为热电材料受到了广泛关注，但其载流子迁移率和热稳定性受天然铜空位的影响。在这项工作中，通过局部化学键增强促进了 CuInTe 热电性能和稳定性的协同改进。 In位点大剂量Mg掺杂可以成功抑制CuInTe中Cu空位的形成，并显着提高其热稳定性。因此，与其他掺杂剂相比，Mg 掺杂表现出通过抑制铜空位来增强晶格结构的显着能力，从而使迁移率显着提高 20%∼50%，并且 CuInMgTe 的值超过 1.2 at 873 K。通过在In位进一步与Ga合金化，热导率大大降低，更令人惊讶的是热稳定性不断增强。值得注意的是，在 Cu(InGa)MgTe 中，在 973 K 处实现了 1.72 的峰值，而在 Cu(InGa)MgTe 中，实现了 0.82 的平均值。这项研究为通过有效的掺杂和缺陷调节来优化铜基三元化合物的热电性能和热稳定性提供了宝贵的见解，为该领域的未来研究提供了指导。