InSb-based semiconductors are potential thermoelectric (TE) materials in the medium temperature range due to their non-toxicity, abundance, excellent process compatibility and stable chemical properties. The mobility of pure InSb is as high as 10⁴–10⁵ cm² V⁻¹ s⁻¹, which results in the ultra-high power factor (PF). However, the lattice thermal conductivity (${\kappa }_l$) is also high because of the intrinsic strong chemical bonding, resulting in a low zT value (∼0.38, at 773 K). In this study, a feasible strategy was adopted to decrease the ${\kappa }_l$ of InSb by embedding Ag/Pt nano particles (NPs) into the InSb bulks. The ${\kappa }_l$ at 703 K was reduced to 2.37 W m⁻¹ K⁻¹ (decrease by ∼40.3%) on account of the enhanced phonon scattering after embedding 2.0% Ag/Pt NPs. Moreover, owing to the synergistic optimization of element doping and energy filtering effects, the PF at 703 K was improved to 5.66 × 10⁻³ W m⁻¹ K⁻² in the InSb+2.0% Ag/Pt NPs sample, which is ∼63.1% higher than that of pristine InSb (3.47 × 10⁻³ W m⁻¹ K⁻²). Ultimately, a remarkably high zT value of 0.81 was achieved at 703 K in the InSb+2.0% Ag/Pt NPs sample, which is ∼92.9% higher than that of the pure InSb. Embedding metastable NPs to achieve multiple effects simultaneously, including the phonon scattering, element doping and energy filtering effects is a feasible means to enhance the zT values, which probably is applicable to other TE materials.

InSb基半导体由于其无毒、丰富、优异的工艺兼容性和稳定的化学性质，是中温范围内潜在的热电（TE）材料。纯InSb的迁移率高达10 ⁴ –10 ⁵  cm ²  V ^-1 s ^-1，这导致了超高的功率因数（PF）。然而，晶格热导率（${\kappa }_l$) 也很高，因为内在的强化学键合，导致zT值低（~0.38，在 773 K）。本研究采用了一种可行的策略来降低${\kappa }_l$通过将 Ag/Pt 纳米颗粒 (NPs) 嵌入 InSb 块体中来制备 InSb。这${\kappa }_l$由于嵌入 2.0% Ag/Pt NPs 后声子散射增强，在 703 K 时的功率降低到 2.37 W m ^-1 K ^-1（降低了～40.3%）。此外，由于元素掺杂和能量过滤效应的协同优化，InSb+2.0% Ag/Pt NPs 样品中 703 K 的PF提高到 5.66 × 10 ^-3  W m ^-1 K ^-2，约为比原始 InSb (3.47 × 10 ^-3  W m ^-1 K ^-2 ) 高 63.1%。最终，一个非常高的zTInSb+2.0% Ag/Pt NPs 样品在 703 K 时达到 0.81 的值，比纯 InSb 高 92.9%。嵌入亚稳态NPs同时实现多种效应，包括声子散射、元素掺杂和能量过滤效应是提高zT值的可行手段，这可能适用于其他TE材料。