Zinc antimonide (ZnSb) is a promising thermoelectric material due to its economic viability, elemental abundance, and superior phase stability compared to other Zn-Sb compounds. However, its widespread application is hindered by a low figure-of-merit (). Extensive research has explored doping, alloying, and nanostructuring to improve . This study investigates the impact of Cr doping in CrZnSb ( = 0.0 – 0.03). Cr doping with = 0.01 significantly reduces lattice thermal conductivity below the phonon glass limit. Debye-Callaway model calculations suggest a combined effect of point defects and decreased grain size caused by Cr incorporation. This reduction translates to enhanced thermoelectric performance, with the = 0.01 sample exhibiting a 70 % improvement in at 673 K, reaching ∼0.67. Exceeding the Cr substitution limit leads to the formation of a detrimental secondary CrSb phase, increasing thermal conductivity. The Single Parabolic Band model calculations predict further enhancement in = 0.01 sample to ∼0.2 at 300 K through optimized carrier concentration (307 % improvement in ). These findings demonstrate the potential for significant improvement in ZnSb via defect engineering and carrier concentration tuning.

中文翻译：

---

通过将晶格热导率降低至声子玻璃极限以下，增强 Cr 掺杂 ZnSb 的热电性能


与其他 Zn-Sb 化合物相比，锑化锌 (ZnSb) 因其经济可行性、元素丰度和优异的相稳定性而成为一种有前途的热电材料。然而，其低品质因数阻碍了其广泛应用。广泛的研究探索了掺杂、合金化和纳米结构来改善。本研究调查了 CrZnSb (= 0.0 – 0.03) 中 Cr 掺杂的影响。 Cr 掺杂量 = 0.01 显着降低晶格热导率低于声子玻璃极限。 Debye-Callaway 模型计算表明点缺陷和 Cr 掺入导致晶粒尺寸减小的综合效应。这种降低转化为热电性能的增强，= 0.01 的样品在 673K​​ 时表现出 70% 的改进，达到~0.67。超过 Cr 替代极限会导致形成有害的二次 CrSb 相，从而增加导热性。单抛物线带模型计算预测，通过优化载流子浓度，在 300K 时，= 0.01 样本将进一步增强至 ∼0.2（改善 307%）。这些发现证明了通过缺陷工程和载流子浓度调节显着改善 ZnSb 的潜力。