3 research outputs found
Bright Fraction of Single-Walled Carbon Nanotubes through Correlated Fluorescence and Topography Measurements
Correlated measurements of fluorescence
and topography were performed
for individual single-walled carbon nanotubes (SWNTs) on quartz using
epifluorescence confocal microscopy and atomic force microscopy (AFM).
Surprisingly, only ∼11% of all SWNTs in DNA-wrapped samples
were found to be highly emissive on quartz, suggesting that the ensemble
fluorescence quantum yield is low because only a small population
of SWNTs fluoresces strongly. Qualitatively similar conclusions were
obtained from control studies using a sodium cholate surfactant system.
To accommodate AFM measurements, excess surfactant was removed from
the substrate. Though individual SWNTs on nonrinsed and rinsed surfaces
displayed differences in fluorescence intensities and line widths,
arising from the influence of the local environment on individual
SWNT optical measurements, photoluminescence data from both samples
displayed consistent trends