Lattice plainification advances highly effective SnSe crystalline thermoelectrics

• 成果类型: Article
• 署名作者: Liu, Dongrui; Wang, Dongyang; Hong, Tao; Wang, Ziyuan; Wang, Yuping; Qin, Yongxin; Su, Lizhong; Yang, Tianyu; Gao, Xiang; Ge, Zhenhua; Qin, Bingchao; Zhao, Li-Dong
• 署名单位: Beihang University; Zhengzhou University; Kunming University of Science & Technology
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9271
• DOI: 10.1126/science.adg7196
• 发表日期: 2023-05-26
• 页码: 841-+
• 关键词: high-performance; power-generation; enhancement; EFFICIENCY; transport; defects; figure; charge; merit; pbte

摘要

Thermoelectric technology has been widely used for key areas, including waste-heat recovery and solid-state cooling. We discovered tin selenide (SnSe) crystals with potential power generation and Peltier cooling performance. The extensive off-stoichiometric defects have a larger impact on the transport properties of SnSe, which motivated us to develop a lattice plainification strategy for defects engineering. We demonstrated that Cu can fill Sn vacancies to weaken defects scattering and boost carrier mobility, facilitating a power factor exceeding similar to 100 microwatts per centimeter per square kelvin and a dimensionless figure of merit (ZT) of similar to 1.5 at 300 kelvin, with an average ZT of similar to 2.2 at 300 to 773 kelvin. We further realized a single-leg efficiency of similar to 12.2% under a temperature difference (DT) of similar to 300 kelvin and a seven-pair Peltier cooling DTmax of similar to 61.2 kelvin at ambient temperature. Our observations are important for practical applications of SnSe crystals in power generation as well as electronic cooling.