EPA Science Inventory

Multi-instrumental characterization of carbon nanotubes dispersed in aqueous solutions

Citation:

Chang, X., Matt Henderson, AND D. Bouchard. Multi-instrumental characterization of carbon nanotubes dispersed in aqueous solutions. Presented at 248th ACS National Meeting and Exposition, San Francisco, CA, August 10 - 14, 2014.

Description:

Previous studies showed that the dispersion extent and physicochemical properties of carbon nanotubes are highly dependent upon the preparation methods (e.g., dispersion methods and dispersants). In the present work, multiwalled carbon nanotubes (MWNTs) are dispersed in aqueous solutions in the presence of surfactants (e.g., sodium dodecyl sulfate and Pluronic), natural organic matters (e.g., Suwannee River humic, Suwannee River fulvic acid), and a polysaccharide (alginate) via ultrasonication or long term magnetic stirring. The prepared MWNTs suspensions are characterized with a variety of instruments to determine their properties and environmental behaviors. Dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AF4) are employed to determine the size and size distribution of prepared samples: Preliminary results indicate that MWNTs suspended in the same solution by ultrasonication and stirring have similar hydrodynamic diameters but quite different size distributions. Quartz crystal microbalance (QCM) and atomic force microscopy (AFM) techniques are employed to evaluate the deposition of MWNTs with different dispersants on crystal sensor surfaces. To evaluate the effects of size and coatings on interactions with model membranes and membranes (e.g., lipid bilayers and cell lines), AF4 fractionated MWNTs sub-samples are further characterized by QCM and AFM to determine their deposition behaviors and changes in membranes mechanical properties, respectively.

Purpose/Objective:

Presented at the 248th ACS National Meeting and Exposition August 10-14, 2014, San Francisco, CA.

URLs/Downloads:

http://www.acs.org/content/acs/en/meetings/fall-2014.html   Exit

Record Details:

Record Type: DOCUMENT (PRESENTATION/SLIDE)
Completion Date: 08/14/2014
Record Last Revised: 08/12/2015
Record Created: 01/30/2015
Record Released: 01/30/2015
OMB Category: Other
Record ID: 305392

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LAB

ECOSYSTEMS RESEARCH DIVISION