Tuning of sorted double-walled carbon nanotubes by electrochemical charging

Martin Kalbac, Alexander A. Green, Mark C. Hersam, Ladislav Kavan

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Double-walled carbon nanotubes sorted by density gradient ultracentrifugation were examined by Raman spectroscopy and by in situ Raman spectroelectrochemistry. The sorted samples had a narrow distribution of diameters of both inner and outer tubes, which enabled a comparison of the behavior of inner metallic tubes and inner semiconducting nanotubes as a function of the applied electrochemical potential. The metallic inner tubes were efficiently doped even though they were protected from electrolyte ions by the outer wall, whereas the doping of semiconducting inner tubes was observed only at high magnitudes of the electrode potential. These results indicate that the doping response of inner tubes is predominantly controlled by inner tube electronic properties. On the other hand, the effect of electronic structure of the outer tube on the behavior of inner tube is weak. Furthermore, the efficiency of the charge transfer from outer to inner wall depends on the doping level. A low doping level corresponds to a high efficiency of the charge-transfer, while a high doping level shows low charge-transfer efficiency.

Original languageEnglish
Pages (from-to)459-469
Number of pages11
JournalACS nano
Volume4
Issue number1
DOIs
Publication statusPublished - Jan 26 2010

    Fingerprint

Keywords

  • Double-walled carbon nanotubes
  • Electrochemical gating
  • Spectroelectrochemistry

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this