The application of the high-entropy concept has generated many interesting results for both alloys and ceramics. However, there are very few reports on high entropy thermoelectric materials. In this work, a single phase high-entropy half-Heusler compound MFe_1-xCo_xSb with 6 equimolar elements (Ti, Zr, Hf, V, Nb and Ta) on the M site was successfully synthesized by a simple method of mechanical alloying, and the single phase was maintained after densification by spark plasma sintering. The multi-elements are homogenously distributed in the samples. The samples are stable and there is no phase separation after annealing at 1073 K in argon for 72 h, which could be attributed to their high configurational entropy. Due to the phonon scattering introduced by multi-elements, the lattice thermal conductivity is largely suppressed with a lowest value of ~ 1.8–1.5 Wm⁻¹K⁻¹ (300–923 K) for MCoSb. By adjusting the Fe/Co ratio, the samples can show both n-type and p-type semiconductor behavior. Maximum zT values of 0.3 and 0.25 are achieved for n-type MCoSb and p-type MFe_0.6Co_0.4Sb, respectively. The results suggest that the high-entropy concept is a promising strategy to extend the composition range and tune the thermoelectric properties for half-Heusler materials, which could potentially be applied in other thermoelectric materials.

高熵概念的应用为合金和陶瓷产生了许多有趣的结果。然而，关于高熵热电材料的报道很少。在这项工作中，单相高熵半赫斯勒化合物 MFe _{1- x} Co _x通过简单的机械合金化方法成功合成了在 M 位具有 6 种等摩尔元素（Ti、Zr、Hf、V、Nb 和 Ta）的 Sb，并通过放电等离子烧结致密化后保持单相。多元素均匀分布在样品中。样品稳定，在氩气中 1073 K 退火 72 小时后没有相分离，这可能归因于它们的高构型熵。由于多元素引入的声子散射，晶格热导率在很大程度上受到抑制，MCoSb 的最低值约为 1.8-1.5 Wm ^-1 K ^-1 (300-923 K)。通过调整 Fe/Co 比，样品可以同时显示 n 型和 p 型半导体行为。最大zT对于 n 型 MCoSb 和 p 型 MFe _0.6 Co _0.4 Sb，分别实现了 0.3 和 0.25 的值。结果表明，高熵概念是一种有前景的策略，可以扩展半赫斯勒材料的组成范围和调整热电性能，这可能会应用于其他热电材料。