Element doping and nano-inclusion embedding are effective approaches to enhance the electrical conductivities and decrease the lattice thermal conductivities of thermoelectric (TE) materials, respectively. However, the intrinsic low electrical thermal conductivities and high electrical properties are severely sacrificed, and the final figure of merit (ZT) is usually restricted. In this study, Ag doping and Pt quantum dot (QD) embedding were synchronously achieved via embedding Ag/Pt alloy QDs into the higher manganese silicides to avoid the conventional single-element doping strategy. The power factor (at 823 K) was enhanced from 1.57 × 10⁻³ W m⁻¹ K⁻² to 1.82 × 10⁻³ W m⁻¹ K⁻² (∼16%) due to the ∼18% increase in carrier concentration that was derived from the Ag doping effect. Simultaneously, the lattice thermal conductivity (at 823 K) decreased from 2.65 W m⁻¹ K⁻¹–1.92 W m⁻¹ K⁻¹ (∼28%) because of the broadband phonon scattering effect that resulted from the residual Pt QDs inclusions. Synthetically, the optimal ZT value increased by ∼52% from 0.42 to 0.64 at 823 K. This study demonstrated that incorporating metastable alloy QDs to obtain element doping and nano-inclusion embedding effects is a novel and feasible means to enhance the ZT value of HMS. This method is also possibly applicable to other alloy QD/TE composites.

元素掺杂和纳米包含物嵌入是分别提高热电（TE）材料的电导率和降低晶格热导率的有效方法。然而，固有的低电导率和高电性能被严重牺牲，并且最终的品质因数（ZT）通常受到限制。在这项研究中，通过将Ag / Pt合金QD嵌入到高锰硅化物中来同步实现Ag掺杂和Pt量子点（QD）嵌入，从而避免了常规的单元素掺杂策略。功率因数（823 K时）从1.57×10 ^-3  W m ^-1  K ^-2提高到1.82×10 ^-3  W m^-1  K ^-2（〜16％），这是由于载流子浓度由于Ag掺杂效应而增加了〜18％。同时，由于残留Pt QDs夹杂物引起的宽带声子散射效应，晶格热导率（在823 K下）从2.65 W m ^-1  K ^-1 –1.92 W m ^-1  K ^-1（〜28％）降低。综合而言，最佳ZT值在823 K时从0.42增加到0.64，增幅约为52％。这项研究表明，掺入亚稳合金QD以获得元素掺杂和纳米夹杂物嵌入效果是提高ZT的一种新颖可行的方法。HMS的价值。该方法也可能适用于其他合金QD / TE复合材料。