As a typical IV-VI compound, SnTe has aroused widely attentions in the thermoelectric community due its similar crystal and band structures with PbTe. However, both the large number of inherent Sn vacancies and high thermal conductivity result in inferior thermoelectric performance in intrinsic SnTe over a broad temperature. In this work, we successfully improved those disadvantages of SnTe via stepwisely Pb heavily alloying and then In doping. A significantly wide fraction of Pb into SnTe (0–50%) achieves multiple effects: (a) the carrier concentration of SnTe is reduced through decreasing Sn vacancies via alloying high solution Pb atoms in the matrix; (b) the band structure is optimized through promoting the convergence of the two valence bands, simultaneously enhancing the Seebeck coefficient; (c) HAADF-STEM coupled with EDS results illustrate that guest Pb atoms randomly and uniformly occupied Sn atomic sites in the matrix, concurrently strengthening the phonon scattering. Furthermore, we introduced indium into Sn_0.6Pb_0.4Te system to create resonant states further enlarging the power factors at low-medium temperature. The integration of bands convergence and DOS distortion achieves a considerably high ZT_ave of ∼0.67 over the wide temperature range of 300–823 K in (Sn_0.6Pb_0.4)_0.995In_0.005Te sample.

作为典型的 IV-VI 化合物，SnTe 因其与 PbTe 相似的晶体和能带结构而在热电界引起了广泛关注。然而，大量的固有 Sn 空位和高热导率导致本征 SnTe 在宽温度范围内的热电性能较差。在这项工作中，我们通过逐步 Pb 重合金化和 In 掺杂成功地改善了 SnTe 的这些缺点。大量 Pb 进入 SnTe (0–50%) 可实现多种效果：(a) 通过减少 Sn 空位来降低 SnTe 的载流子浓度在基体中合金化高固溶铅原子；(b) 通过促进两个价带的收敛优化能带结构，同时提高塞贝克系数；(c) HAADF-STEM 结合 EDS 结果表明客体 Pb 原子随机且均匀地占据基质中的 Sn 原子位点，同时增强声子散射。此外，我们将铟引入 Sn _0.6 Pb _0.4 Te 系统以产生谐振状态，进一步扩大中低温下的功率因数。在300–823 K in (Sn _0.6 Pb _0.4 ) _0.995的宽温度范围内，能带收敛和 DOS 失真的集成实现了相当高的ZT _{ave ～} 0.67在_0.005 Te 样品中。