期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2019
卷号:116
期号:44
页码:21998-22003
DOI:10.1073/pnas.1911085116
出版社:The National Academy of Sciences of the United States of America
摘要:We report enhanced thermoelectric performance of SnTe by further increasing its intrinsic high carrier concentration caused by Sn vacancies in contrast to the traditional method. Along with In 2 Te 3 alloying, which results in an enhanced Seebeck coefficient, Li 2 Te is added to further increase the carrier concentration in order to maintain high electrical conductivity. Finally, a relatively high PF ave of ∼28 μW cm −1 K −2 in the range between 300 and 873 K is obtained in an optimized SnTe-based compound. Furthermore, nanoprecipitates with extremely high density are constructed to scatter phonons strongly, resulting in an ultralow lattice thermal conductivity of ∼0.45 W m −1 K −1 at 873 K. Given that the Z value is temperature dependent, the ( ZT ) eng and ( PF ) eng values are adopted to accurately predict the performance of this material. Taking into account the Joule and Thomson heat, output power density of ∼5.53 W cm −2 and leg efficiency of ∼9.6% are calculated for (SnTe) 2.94 (In 2 Te 3 ) 0.02 -(Li 2 Te) 0.045 with a leg length of 4 mm and cold- and hot-side temperatures of 300 and 870 K, respectively..
关键词:SnTe ; resonant level ; nanoprecipitate ; output power density ; efficiency