当前位置: X-MOL 学术Energy Environ. Sci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Breaking the sodium solubility limit for extraordinary thermoelectric performance in p-type PbTe
Energy & Environmental Science ( IF 32.5 ) Pub Date : 2022-07-30 , DOI: 10.1039/d2ee01421a
Ying Cai Zhu , Lei Hu , Shaoping Zhan , Toshiaki Ina , Xiang Gao , Tao Hong , Li-Dong Zhao

The thermoelectric performance of a given material is closely related to its carrier concentration. However, the maximum solubility of dopants in matrixes is a key limitation for improving the carrier concentration, which may result in an underestimated figure-of-merit ZT. Here we show that Na solubility in the PbTe–x% AgInSe2 (LISST) system is largely enhanced exceeding its conventional solubility limit. The enhanced Na solubility facilitates band convergence corroborated by the Pisarenko relationship and temperature-dependent Hall coefficient measurements. Accordingly, we achieve a large power factor of ∼28.4 μW cm−1 K−2 at 873 K for Pb0.95Na0.05Te–0.5% AgInSe2. In addition, the lattice thermal conductivity is suppressed with increasing Na content. Hence, the quality factor is largely boosted especially at high temperatures due to the enhanced weighted mobility and depressed lattice thermal conductivity. Consequently, an ultrahigh figure-of-merit ZT of ∼2.5 at 773 K and a large average ZT (ZTavg) of ∼1.5 at 323–873 K are achieved in Pb0.95Na0.05Te–0.5% AgInSe2. Our findings demonstrate that a synergistic optimization of electrical and thermal properties can be realized through breaking the solubility limit of the doped component, providing a promising path for the enhancement of thermoelectric performance.

中文翻译:

打破钠溶解度极限以实现 p 型 PbTe 中非凡的热电性能

给定材料的热电性能与其载流子浓度密切相关。然而,掺杂剂在基质中的最大溶解度是提高载流子浓度的关键限制,这可能导致品质因数ZT被低估。在这里,我们展示了 PbTe- x % AgInSe 2 (LISST) 体系中的 Na 溶解度大大提高,超过了其传统的溶解度极限。增强的 Na 溶解度促进了 Pisarenko 关系和温度相关霍尔系数测量证实的带收敛。因此,对于 Pb 0.95 Na 0.05 ,我们在 873 K 时实现了 ~28.4 μW cm -1 K -2的大功率因数Te–0.5% AgInSe 2。此外,随着Na含量的增加,晶格热导率受到抑制。因此,由于增强的加权迁移率和降低的晶格热导率,品质因数大大提高,特别是在高温下。因此,在 Pb 0.95 Na 0.05 Te–0.5% AgInSe 2中实现了在 773 K 时约为 2.5的超高品质因数ZT和在 323-873 K 时约为 1.5的大平均ZT ( ZT avg ). 我们的研究结果表明,通过打破掺杂组分的溶解度极限,可以实现电学和热学性能的协同优化,为提高热电性能提供了一条有希望的途径。
更新日期:2022-07-30
down
wechat
bug