Digenite (Cu_1.8S) as a potential p-type thermoelectric (TE) material has attracted extensive attention due to its environmental benign, abundant resources and low cost of component elements. In this study, the TE properties of Mn_xCu_1.8S bulk samples prepared by mechanical alloying (MA) combined with spark plasma sintering (SPS) were investigated. Doping Mn would initially substitute Cu and tune the band structure of Cu_1.8S with an enlarged band gap E_g. However, if Mn content is beyond the solubility limit of x = 0.01 in Cu_1.8S will cause the formation of MnS, which contributes to the formation of Cu-rich phases at 0.02 ≤ x ≤ 0.08. Benefiting from the synergetic scattering effect of point defects (${\text{Mn}}_{\text{Cu}}^{•}$, ${\text{V}}_{\text{S}}^{••}$) and MnS, Cu_1.96S, Cu_1.97S, Cu₂S phases, the lowest thermal conductivity κ value of 0.75 W m⁻¹K⁻¹ was obtained at 773 K for Mn_0.08Cu_1.8S. Along with the decreased κ, the highest figure of merit ZT value of 0.92 at 773 K achieved in Mn_0.08Cu_1.8S bulk sample. A maximum engineering ZT_eng of 0.3 and its efficiency η_max of about 6% were obtained at 323–773 K, which is almost 3 times than that of the pristine Cu_1.8S (η_max = 2.2%). Introducing Mn in Cu_1.8S is an effective and convenient strategy to improve TE performance.

作为一种潜在的p型热电（TE）材料，Digenite（Cu _1.8 S）由于其环境友好，资源丰富和组成元件成本低而受到广泛关注。在这项研究中，研究了通过机械合金化（MA）结合火花等离子体烧结（SPS）制备的Mn _x Cu _1.8 S块状样品的TE特性。掺杂Mn最初会替代Cu，并以更大的带隙E _g调整Cu _1.8 S的能带结构。但是，如果Mn含量超出 Cu _1.8中x的溶解度极限x = 0.01S将导致MnS的生成，其在0.02≤有助于富-铜相的形成X  ≤0.08。受益于点缺陷的协同散射效应（${\text{锰}}_{\text{铜}}^{•}$， ${\text{V}}_{\text{小号}}^{••}$）和的MnS，铜_1.96 S，铜_1.97 S，的Cu ₂ S期，最低的热导率κ为0.75脉冲W M的值^-1 ķ ^-1在773ķ获得的Mn _0.08铜_1.8 S.随着下降κ，Mn _0.08 Cu _1.8 S块状样品在773 K时的最高品质因数ZT值为0.92 。最大工程ZT_主机的0.3和其效率η_最高在323-773 K，这几乎是3倍于原始的Cu，获得的约6％_1.8 S（η_最大值 = 2.2％）。在Cu _1.8 S中引入Mn是提高TE性能的有效且方便的策略。