Thermoelectric properties of single-wall carbon nanotube networks. (24th June 2019)

• Record Type: Journal Article
• Authors: Hayashi, Daisuke; Nakai, Yusuke; Kyakuno, Haruka; Hongo, Naoya; Miyata, Yasumitsu; Yanagi, Kazuhiro; Maniwa, Yutaka
• Is Part Of: Japanese journal of applied physics. Volume 58:Number 7(2019)
• Publication Date: 2019-06-24
• Subjects: Seebeck coefficient -- power factor -- thermoelectric properties -- carbon nanotube -- SWCNT -- simulation -- non-equilibrium Green's function theory; Physics -- Periodicals; 621.05
• DOI: 10.7567/1347-4065/ab2408
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The Seebeck coefficient S and power factor P of single-wall carbon nanotube (SWCNT) networks were systematically investigated as a function of chemical potential μ, based on theoretical simulations employing non-equilibrium Green's function theory. The results focused on the gap regions of semiconducting (s-)SWCNTs. The thermoelectric properties of individual SWCNTs were classified into three groups: s-SWCNTs, metallic (m-)SWCNTs, and pseudo-metallic SWCNTs. The maximum values of P for individual s-SWCNTs was independent of SWCNT diameter. In parallel and serial networks of SWCNTs, S and P were found to be very sensitive to the amount of m-SWCNTs, as well as the SWCNT diameter distributions. A comparison with experimental results suggested that an SWCNT bundle can be modeled as a "rope" with an equivalent S calculated for parallel circuits. The presence of SWCNT junctions in the films substantially reduced the P value from those of the composing SWCNTs while S was almost unvaried.