Huang Wenxin, Tokunaga Eriko, Nakashima Yuki, Fujigaya Tsuyohiko
Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka, Japan.
The World Premier International Research Center Initiative, International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka, Japan.
Sci Technol Adv Mater. 2019 Mar 1;20(1):97-104. doi: 10.1080/14686996.2019.1567107. eCollection 2019.
Single-walled carbon nanotubes (SWNTs), especially their semiconducting type, are promising thermoelectric (TE) materials due to their high Seebeck coefficient. In this study, the in-plane Seebeck coefficient (), electrical conductivity (), and thermal conductivity () of sorted semiconducting SWNT (s-SWNT) free-standing sheets with different s-SWNT purities are measured to determine the figure of merit We find that the value of the sheets increases with increasing s-SWNT purity, mainly due to an increase in Seebeck coefficient while the thermal conductivity remaining constant, which experimentally proved the superiority of the high purity s-SWNT as TE materials for the first time. In addition, from the comparison between sorted and unsorted SWNT sheets, it is recognized that the difference of between unsorted SWNT and high-purity s-SWNT sheet is not remarkable, which suggests the control of carrier density is necessary to further clarify the superiority of SWNT sorting for TE applications.
单壁碳纳米管（SWNTs），尤其是其半导体类型，因其高塞贝克系数而有望成为热电（TE）材料。在本研究中，测量了具有不同s-SWNT纯度的分选半导体SWNT（s-SWNT）独立薄膜的面内塞贝克系数（）、电导率（）和热导率（），以确定优值。我们发现，薄膜的 值随着s-SWNT纯度的增加而增加，这主要是由于塞贝克系数的增加，而热导率保持不变，这首次通过实验证明了高纯度s-SWNT作为TE材料的优越性。此外，通过对分选和未分选SWNT薄膜的比较，认识到未分选SWNT和高纯度s-SWNT薄膜之间的 差异并不显著，这表明控制载流子密度对于进一步阐明SWNT分选在TE应用中的优越性是必要的。
