Band gap fluorescence from individual single-walled carbon nanotubes

Research areas:
  • Uncategorized
Year: 2002
Type of Publication: Article
Authors:
  • O', M. J.
  • Connell, C. B. Huffman S. M. Bachilo
Journal: Science Volume: 297
Number: 5581 Pages: 593-596
Month: JUL 26 2002
Note:
PT: J; TC: 2032; UT: WOS:000177054200048
Abstract:
Fluorescence has been observed directly across the band gap of semiconducting carbon nanotubes. We obtained individual nanotubes, each encased in a cylindrical micelle, by ultrasonically agitating an aqueous dispersion of raw single-walled carbon nanotubes in sodium dodecyl sulfate and then centrifuging to remove tube bundles, ropes, and residual catalyst. Aggregation of nanotubes into bundles otherwise quenches the fluorescence through interactions with metallic tubes and substantially broadens the absorption spectra. At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap selective protonation of the side walls of the tube. This protonation is readily reversed by treatment with base or ultraviolet light.