Se-free n-type (Bi,Sb)₂Te₃ thermoelectric materials, outperforming traditional n-type Bi₂(Te,Se)₃, emerge as a compelling candidate for practical applications of recovering low-grade waste heat. A 100% improvement in the maximum ZT of n-type Bi_1.7Sb_0.3Te₃ is demonstrated by using melt-spinning and excess Te-assisted transient liquid phase sintering (LPS). Te-rich sintering promotes the formation of intrinsic defects (Te_Bi), elevating the carrier concentration and enhancing the electrical conductivity. Melt-spinning with excess Te fine-tunes the electronic band, resulting in a high power-factor of 0.35 × 10^–3 W·m^–1 K^–2 at 300 K. Rapid volume change during sintering induces the formation of dislocation networks, significantly suppressing the lattice thermal conductivity (0.4 W·m^–1 K^–1). The developed n-type legs achieve a high maximum ZT of 1.0 at 450 K resulting in a 70% improvement in the output power of the thermoelectric device (7.7 W at a temperature difference of 250 K). This work highlights the synergy between melt-spinning and transient LPS, advancing the tailored control of both electronic and thermal properties in thermoelectric technology.

中文翻译：

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热电无硒 n 型 (Bi,Sb)2Te3 中电子和热传输的协同调控


无硒n型(Bi,Sb) ₂ Te ₃ 热电材料，优于传统n型Bi ₂ (Te,Se) ₃ ，成为回收低品位废热实际应用的引人注目的候选者。通过使用熔体纺丝和过量的Te辅助瞬态液体，证明了n型Bi _1.7 Sb _0.3 Te ₃ 的最大ZT提高了100%相烧结（LPS）。富Te烧结促进了本征缺陷（Te _Bi ）的形成，提高了载流子浓度并增强了电导率。过量 Te 的熔融纺丝可以微调电子能带，从而在300 K。烧结过程中快速的体积变化导致位错网络的形成，显着抑制晶格热导率（0.4 W·m ^–1 K ^–1 ）。所开发的 n 型臂在 450 K 时实现了 1.0 的最高 ZT，从而使热电装置的输出功率提高了 70%（在 250 K 温差时为 7.7 W）。这项工作强调了熔体纺丝和瞬态 LPS 之间的协同作用，推进了热电技术中电子和热性能的定制控制。