Thermal Conductivity of Chirality-Sorted Carbon Nanotube Networks

TL;DR

This study investigates how the thermal conductivity of chirality-sorted single-walled carbon nanotube networks depends on network morphology rather than chirality, revealing high thermal conductivities comparable to metals with lower mass density.

Contribution

It provides the first experimental analysis showing thermal conductivity in SWNT networks is influenced by morphology, not chirality, and quantifies this relationship.

Findings

Thermal conductivities range from 80 to 370 W/m/K.

Conductivity depends on network morphology, not chirality.

High thermal conductivities comparable to metals with lower mass density.

Abstract

The thermal properties of single-walled carbon nanotubes (SWNTs) are of significant interest, yet their dependence on SWNT chirality has been, until now, not explored experimentally. Here we used electrical heating and infrared thermal imaging to simultaneously study thermal and electrical transport in chirality-sorted SWNT networks. We examined solution processed 90% semiconducting, 90% metallic, purified unsorted (66% semiconducting), and as-grown HiPco SWNT films. The thermal conductivities of these films range from 80 to 370 W/m/K but are not controlled by chirality, instead being dependent on the morphology (i.e. mass and junction density, quasi-alignment) of the networks. The upper range of the thermal conductivities measured is comparable to that of the best metals (Cu and Ag) but with over an order of magnitude lower mass density. This study reveals important factors controlling the thermal properties of light-weight chirality-sorted SWNT films, for potential thermal and thermoelectric applications.