Brightly Fluorescent Single-Walled Carbon Nanotubes via an Oxygen-Excluding Surfactant Organization
Sang-Yong Ju,1
William P. Kopcha,2
Fotios Papadimitrakopoulos1,2*
Attaining high photoluminescence quantum yields for single-walled
carbon nanotubes (SWNTs) in order to broaden their optoelectronics
and sensing applications has been a challenging task. Among
various nonradiative pathways, sidewall chemisorption of oxygen
provides a known defect for exciton quenching through nanotube
hole doping. We found that an aliphatic (dodecyl) analog of
flavin mononucleotide, FC12, leads to high dispersion of SWNTs,
which tend to aggregate into bundles. Unlike other surfactants,
the surface organization of FC12 is sufficiently tight to exclude
oxygen from the SWNT surface, which led to quantum yields as
high as 20%. Toluene-dispersed, FC12-wrapped nanotubes exhibited
an absorption spectrum with ultrasharp peaks (widths of 12 to
25 milli–electron volts) devoid of the characteristic
background absorption of most nanotube dispersions.
2 Department of Chemistry, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
* To whom correspondence should be addressed. E-mail: papadim{at}mail.ims.uconn.edu
