Deng Qian, Shi Xiao-Lei, Li Meng, Tan Xiaobo, Li Ruiheng, Wang Chen, Chen Yue, Dong Hongliang, Ang Ran, Chen Zhi-Gang
Key Laboratory of Radiation Physics and Technology, Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, China.
School of Chemistry and Physics, ARC Research Hub in Zero-emission Power Generation for Carbon Neutrality, and Centre for Materials Science, Queensland University of Technology, Brisbane, QLD, Australia.
Nat Commun. 2025 Jan 14;16(1):656. doi: 10.1038/s41467-025-56003-9.
Te-free thermoelectrics have garnered significant interest due to their immense thermoelectric potential and low cost. However, most Te-free thermoelectrics have relatively low performance because of the strong electrical and thermal transport conflicts and unsatisfactory compatibility of interfaces between device materials. Here, we develop lattice defect engineering through Cu doping to realize a record-high figure of merit of ~1.9 in n-type polycrystalline PbSe. Detailed micro/nanostructural characterizations and first-principles calculations demonstrate that Cu-induced interstitial defects and nanoprecipitates simultaneously optimize electron and phonon transport properties. Moreover, a robust Co/PbSe interface is designed to effectively prevent chemical reactions/diffusion; this interface exhibited a low electrical contact resistivity of ~10.9 μΩ cm, excellent durability, and good stability in the thermoelectric module, which achieves a record-high conversion efficiency of 13.1% at a temperature difference of 460 K in segmented thermoelectric modules. This study lays the groundwork for advancing the development of Te-free selenide-based thermoelectric materials.
无碲热电材料因其巨大的热电潜力和低成本而备受关注。然而，由于强烈的电输运和热输运冲突以及器件材料之间界面兼容性不佳，大多数无碲热电材料的性能相对较低。在此，我们通过铜掺杂开展晶格缺陷工程，以在n型多晶PbSe中实现高达约1.9的优值记录。详细的微观/纳米结构表征和第一性原理计算表明，铜诱导的间隙缺陷和纳米析出物同时优化了电子和声子输运特性。此外，设计了一个坚固的Co/PbSe界面以有效防止化学反应/扩散；该界面在热电模块中表现出约10.9 μΩ·cm的低电接触电阻率、优异的耐久性和良好的稳定性，在分段热电模块中，在460 K的温差下实现了13.1%的创纪录高转换效率。本研究为推进无碲硒化物基热电材料的发展奠定了基础。
