Faculty of Science, Institute of Physical and Engineering Science, Kunming University of Science and Technology, Kunming 650500, China.
College of Chemistry and Materials Science, Hubei Engineering University, Xiaogan 432000, China.
Molecules. 2023 Mar 14;28(6):2629. doi: 10.3390/molecules28062629.
Thermoelectric (TE) technology, which can convert scrap heat into electricity, has attracted considerable attention. However, broader applications of TE are hindered by lacking high-performance thermoelectric materials, which can be effectively progressed by regulating the carrier concentration. In this work, a series of PbSe(NaCl) (x = 3, 3.5, 4, 4.5) samples were synthesized through the NaCl salt-assisted approach with Na and Cl doped into their lattice. Both theoretical and experimental results demonstrate that manipulating the carrier concentration by adjusting the content of NaCl is conducive to upgrading the electrical transport properties of the materials. The carrier concentration elevated from 2.71 × 10 cm to 4.16 × 10 cm, and the materials demonstrated a maximum power factor of 2.9 × 10 W m K. Combined with an ultralow lattice thermal conductivity of 0.7 W m K, a high thermoelectric figure of merit (T) with 1.26 at 690 K was attained in PbSe(NaCl). This study provides a guideline for chemical doping to improve the thermoelectric properties of PbSe further and promote its applications.
热电（TE）技术可以将废热转化为电能，引起了相当大的关注。然而，缺乏高性能的热电材料限制了 TE 的更广泛应用，而通过调节载流子浓度可以有效地推进这一进程。在这项工作中，通过 NaCl 盐辅助方法合成了一系列 PbSe(NaCl)（x = 3、3.5、4、4.5）样品，其中 Na 和 Cl 掺杂到晶格中。理论和实验结果均表明，通过调整 NaCl 的含量来操纵载流子浓度有利于提升材料的电子输运性能。载流子浓度从 2.71×1017 cm-3 提升到 4.16×1017 cm-3，材料表现出最大的功率因子为 2.9×10-3 W m-1 K-1。结合超低晶格热导率 0.7 W m-1 K-1，在 PbSe(NaCl)中获得了 690 K 时高达 1.26 的高热电优值（ZT）。本研究为进一步通过化学掺杂来改善 PbSe 的热电性能提供了指导，并促进了其应用。
