Individual single-walled nanotubes and hydrogels made by oxidative exfoliation of carbon nanotube ropes

Nina I. Kovtyukhova, Thomas E. Mallouk, Ling Pan, Elizabeth C. Dickey

Research output: Contribution to journalArticle

310 Scopus citations

Abstract

Single-walled carbon nanotubes were oxidized by a technique previously developed for the oxidation of graphite to graphite oxide (GO). This process involves treatment with concentrated H2SO4 containing (NH4)2S2O8 and P2O 5, followed by H2SO4 and KMnO4. Oxidation results in complete exfoliation of nanotube ropes to yield individual oxidized tubes that are 40-500 nm long. The C:O:H atomic ratio of vacuum-dried oxidized nanotubes is approximately 2.7:1.0:1.2. XPS and IR spectra show evidence for surface O - H, C = O, and COOH groups. The oxidized nanotubes slowly form viscous hydrogels at unusually low concentration (≥0.3 wt %), and this behavior is attributed to the formation of a hydrogen-bonded nanotube network, The oxidized tubes bind readily to amine-coated surfaces, on which they adsorb as smooth and dense monolayer films. Thin films of the oxidized nanotubes show ohmic current-voltage behavior, with resistivities in the range of 0.2-0.5 Ω-cm.

Original languageEnglish (US)
Pages (from-to)9761-9769
Number of pages9
JournalJournal of the American Chemical Society
Volume125
Issue number32
DOIs
StatePublished - Aug 13 2003

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Fingerprint Dive into the research topics of 'Individual single-walled nanotubes and hydrogels made by oxidative exfoliation of carbon nanotube ropes'. Together they form a unique fingerprint.

  • Cite this