Phonon transport assisted by inter-tube carbon displacements in carbon nanotube mats. Academic Article uri icon

abstract

  • Thermal transport in carbon nanotube (CNT) mats, consisting of randomly networked multi-walled carbon nanotubes (MWNTs), is not as efficient as in an individual CNT because of the constrained tube-to-tube phonon transport. Through experiments and modeling, we discover that phonon transport in CNT mats is significantly improved by ion irradiation, which introduces inter-tube displacements, acting as stable point contacts between neighboring tubes. Inter-tube displacement-mediated phonon transport enhances conductivity, while inter-tube phonon-defect scattering reduces conductivity. At low ion irradiation fluence, inter-tube thermal transport enhancement leads to thermal conductivity increase by factor>5, while at high ion irradiation fluence point defects within tubes cause a decrease in thermal conductivity. Molecular dynamics simulations support the experimentally obtained results and the proposed mechanisms. Further conductivity enhancement in irradiated mats was obtained by post-irradiation heat treatment that removes majority of the defects within the tubes without affecting thermally stable inter-tube displacements.

published proceedings

  • Sci Rep

altmetric score

  • 0.25

author list (cited authors)

  • Aitkaliyeva, A., Chen, D. i., & Shao, L.

citation count

  • 19

complete list of authors

  • Aitkaliyeva, Assel||Chen, Di||Shao, Lin

publication date

  • September 2013