Model polymer composites of DNA wrapped single-wall carbon nanotubes (SWNTs) dispersed in polyacrylic acid are used for a systematic comparison of the different metrologies currently used to evaluate SWNT dispersion. Application of a pH-controlled variation in dispersion quality has allowed for the evaluation of each method in terms of its sensitivity to SWNT bundling and clustering in the limit of nanodispersion. Small-angle neutron scattering (SANS) was found to provide the most direct measure of dispersion, followed by near-infrared fluorescence spectroscopy, optical absorption spectroscopy, and resonant Raman scattering. Our results represent the first systematic comparison of currently accepted metrics for assessing SWNT dispersion and provide a calibration of the various techniques.
Citation: Journal of Physical Chemistry
Pub Type: Journals
composite, dispersion, nanotube, neutron scattering, polyarylic acid, polymer