Jump to main content
Jump to site search

Issue 16, 2018
Previous Article Next Article

Cooperative inter- and intra-layer lattice dynamics of photoexcited multi-walled carbon nanotubes studied by ultrafast electron diffraction

Author affiliations

Abstract

Optical tuning and probing ultrafast structural response of nanomaterials driven by electronic excitation constitute a challenging but promising approach for understanding microscopic mechanisms and applications in microelectromechanical systems and optoelectrical devices. Here we use pulsed electron diffraction in a transmission electron microscope to investigate laser-induced tubular lattice dynamics of multi-walled carbon nanotubes (MWCNTs) with varying laser fluence and initial specimen temperature. Our photoexcitation experiments demonstrate cooperative and inverse collective atomic motions in intralayer and interlayer directions, whose strengths and rates depend on pump fluence. The electron-driven and thermally driven structural responses with opposite amplitudes cause a crossover between intralayer and interlayer directions. Our ab initio calculations support these findings and reveal that electrons excited from π to π* orbitals in a carbon tube weaken the intralayer bonds while strengthening the interlayer bonds along the radial direction. Moreover, by probing the structural dynamics of MWCNTs at initial temperatures of 300 and 100 K, we uncover the concomitance of thermal and nonthermal dynamical processes and their mutual influence in MWCNTs. Our results illustrate the nature of electron-driven nonthermal process and electron–phonon thermalization in the MWCNTs, and bear implications for the intricate energy conversion and transfer in materials at the nanoscale.

Graphical abstract: Cooperative inter- and intra-layer lattice dynamics of photoexcited multi-walled carbon nanotubes studied by ultrafast electron diffraction

Back to tab navigation

Supplementary files

Publication details

The article was received on 16 Jan 2018, accepted on 18 Mar 2018 and first published on 19 Mar 2018


Article type: Paper
DOI: 10.1039/C8NR00432C
Citation: Nanoscale, 2018,10, 7465-7471
  •   Request permissions

    Cooperative inter- and intra-layer lattice dynamics of photoexcited multi-walled carbon nanotubes studied by ultrafast electron diffraction

    S. Sun, Z. Li, Z. Li, R. Xiao, M. Zhang, H. Tian, H. Yang and J. Li, Nanoscale, 2018, 10, 7465
    DOI: 10.1039/C8NR00432C

Search articles by author

Spotlight

Advertisements