SnTe is a kind of promising candidates for medium temperature thermoelectric materials, while its thermoelectric properties are limited by not only the poor electrical transport properties caused by intrinsic high carrier concentration and large valence bands offset, but also the relatively high lattice thermal conductivity. In this work, the thermoelectric performance of Mn–Bi and Mn–Sb co-doped SnTe is investigated. As expected, Mn doping decreases the energy separation between the two valence band maxima, enabling improved Seebeck coefficient, the donor effect of Bi or Sb weakens the adverse effect of Mn doping on carrier concentration, and then a relatively high average power factor is achieved. More importantly, a variety of defects, including point defects, dislocations and nanoprecipitates, are introduced, which can scatter phonons in a wide frequency range and decrease the lattice thermal conductivity. Finally, the synergy of these effects yields a maximum ZT of 1.14 at 873 K and an average ZT of 0.7 (300–873 K) in Sn_0·88Bi_0·04Mn_0·08Te sample, and a maximum ZT of 1.23 at 873 K and an average ZT of 0.73 (300–873 K) in Sn_0·82Sb_0·06Mn_0·12Te sample.

SnTe 是一种很有前景的中温热电材料，但其热电性能不仅受到本征高载流子浓度和大价带偏移导致的较差的电传输性能的限制，而且还受到相对较高的晶格热导率的限制。在这项工作中，研究了 Mn-Bi 和 Mn-Sb 共掺杂 SnTe 的热电性能。正如预期的那样，Mn 掺杂降低了两个价带最大值之间的能量分离，从而提高了塞贝克系数，Bi 或 Sb 的施主效应减弱了 Mn 掺杂对载流子浓度的不利影响，从而实现了相对较高的平均功率因数。更重要的是，引入了多种缺陷，包括点缺陷、位错和纳米沉淀物，它可以在很宽的频率范围内散射声子并降低晶格热导率。最后，这些效应的协同作用产生了最大的在 Sn _0·88 Bi _0·04 Mn _0·08 Te 样品中，873 K 时的ZT为 1.14，平均ZT为 0.7 (300-873 K) ，873 K 时的最大ZT为 1.23，平均ZT为 0.73 ( 300–873 K) 在 Sn _0·82 Sb _0·06 Mn _0·12 Te 样品中。