GeTe is an excellent mid-temperature thermoelectric material with various freedom degrees to tune the thermoelectric performance, which has drawn intensive attentions. Herein, superior thermoelectric performance of GeTe-based materials is achieved through significantly elevating quality factor B with FeTe₂ introduction. First-principles calculations show that introducing FeTe₂ into GeTe can increase the density of states due to the contribution of the 3d orbital of Fe, leading to an enhancement of effective mass from ∼2.21m₀ in Fe-free sample to ∼3.01 m₀ in Ge_0.9Sb_0.1Te–2%FeTe₂, which could maintain high electrical transport properties. Meanwhile, the lattice thermal conductivity is drastically suppressed by Van der Waals gaps, Fe-rich nanoprecipitates and strain field fluctuations with minimal disruption on carrier transport, leading to a minimum lattice thermal conductivity of ∼0.54 Wm^-1 K⁻¹. Ultimately, a superior ZT ∼2.1 at 723 K and a ZT_ave of ∼1.25 at 300–773 K are attained in Ge_0.9Sb_0.1Te–1%FeTe₂.

GeTe是一种优异的中温热电材料，具有多种调节热电性能的自由度，引起了广泛关注。在此，通过引入FeTe ₂显着提高品质因数B实现了 GeTe 基材料的优异热电性能。第一原理计算显示，引入FETE ₂成的GeTe可以增加态密度由于3d轨道的Fe的贡献，从~2.21导致有效质量的增强米₀的Fe-免费样品中~3.01米₀在 Ge _0.9 Sb _0.1 Te–2% FeTe ₂，可以保持高电传输性能。同时，晶格热导率被范德华间隙、富铁纳米沉淀物和应变场波动显着抑制，对载流子传输的干扰最小，导致最小晶格热导率约为 0.54 Wm ^-1 K ^-1。最终，在 Ge _0.9 Sb _0.1 Te–1%FeTe ₂中获得了在 723 K 下的优越ZT ∼2.1 和在 300–773 K 下的ZT _ave ∼1.25 。