The well converged transporting valence bands in SnTe-MnTe alloys ensures a superior electronic performance, while their thermal transport properties still need to be further optimized for higher thermoelectric performance. Herein, the mechanical alloying is utilized to fabricate the SnTe-15%MnTe-2%Bi alloys, leading to a remarkable reduction of grain size as well as the formation of dense dislocations. Unexpectedly, the solubility of MnTe is reduced to ∼6% by mechanical alloying at room temperature, inducing an enhanced phonon scattering from nanoprecipitates. These full-scale hierarchical microstructures effectively decrease the lattice thermal conductivity of SnTe-15%MnTe-2%Bi to ∼0.5 W m⁻¹ K⁻¹ at 850 K. In addition, the increased vacancy formation energy triggers a reduction in carrier concentration (∼3 × 10¹⁹ cm⁻³) due to the decreased MnTe content in matrix. Moreover, the energy filtering effect through precipitate-matrix interface enables an improvement in Seebeck coefficient. Accordingly, the figure of merit of SnTe-15%MnTe-2%Bi is dramatically increased to ∼1.5 at 850 K by mechanical alloying. This work clearly demonstrates that mechanical alloying changes the composition and microstructure of materials, which significantly affect the thermoelectric transport properties, enabling an obvious performance enhancement.

SnTe-MnTe合金中很好地收敛的传输价带确保了优异的电子性能，而它们的热传输性能仍需要进一步优化以获得更高的热电性能。在本文中，利用机械合金化来制造SnTe-15％MnTe-2％Bi合金，从而导致晶粒尺寸显着减小以及致密位错的形成。出乎意料的是，在室温下通过机械合金化将MnTe的溶解度降低至约6％，从而导致纳米沉淀物中声子的散射增强。这些全面的分层微结构有效地将SnTe-15％MnTe-2％Bi的晶格热导率降低至约0.5 W m ^-1  K ^-1此外，由于基质中MnTe含量降低，空位形成能的增加触发了载流子浓度的降低（〜3×10 ¹⁹  cm ^-3）。此外，通过沉淀物-基质界面的能量过滤效果可以改善塞贝克系数。因此，通过机械合金化，SnTe-15％MnTe-2％Bi的品质因数在850 K时显着增加至〜1.5。这项工作清楚地表明，机械合金化会改变材料的组成和微观结构，从而显着影响热电传输性能，从而显着提高性能。