Lead‐free polycrystalline manganese telluride holds great potential in the development of waste heat recovery due to its fascinating physical properties. However, the poor thermoelectric (TE) performance in the p‐type MnTe alloys always results from their inferior carrier concentration, leading to low power factor and high thermal conductivity which restrict the overall thermoelectric performance. In this work, the problem is solved by decoupling its electrical and thermal transports through the hole donor Ge‐deficiency in MnTe + x mol.% GeTe (0 ≤ x ≤ 4) compounds. Intrinsically, extra GeTe in MnTe + x mol.% GeTe compound offers free charge carriers due to a narrow bandgap comparatively, realizing not only a full assessment of stimulated electrical performance but also an enhanced power factor. Moreover, benefiting from the nano‐precipitates and tweed microstructures, the lattice thermal conductivity effectively reduces due to the intensive phonon scattering accordingly. Ultimately, a maximum ZT of ≈1.2 at 873 K in the 3 mol.% GeTe doped MnTe sample is realized.

中文翻译：

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通过电和热传输的解耦增强 MnTe 的热电性能

无铅多晶碲化锰由于其迷人的物理特性，在余热回收领域的发展中具有巨大的潜力。然而，p型MnTe合金的热电（TE）性能较差，往往是由于载流子浓度较低，导致功率因数低和热导率高，从而限制了整体热电性能。在这项工作中，通过 MnTe + 中的空穴供体 Ge 缺陷解耦其电和热传输来解决该问题Xmol.% GeTe (0 ≤X≤ 4) 化合物。本质上，MnTe + 中含有额外的 GeTeX由于带隙相对较窄，mol.% GeTe 化合物提供自由载流子，不仅实现了受激电性能的全面评估，而且还提高了功率因数。此外，受益于纳米沉淀物和粗花呢微观结构，由于声子散射密集，晶格热导率有效降低。最终，在 3 mol.% GeTe 掺杂的 MnTe 样品中，在 873 K 时实现了约 1.2 的最大 ZT。