1616-3028/asset/cover.gif?v=1&s=aa0e18d3cb78e9b2ca8405559bd0b600d037e2d3 "Advanced Functional Materials")
This work is supported by the Ministry of Education, Science and Technology of Korea through the Basic Atomic Energy Research Institute (BAERI) program, the basic science research program (R-01-2008-000-10219-0) and the CNRF project. This work utilized facilities supported in part by the National Science Foundation (DMR-9986442). The mention of commercial products does not imply endorsement by NIST, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose. Supporting Information is available online from Wiley InterScience or from the authors.
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Full Paper
Charged Rod-Like Nanoparticles Assisting Single-Walled Carbon Nanotube Dispersion in Water†
Article first published online: 1 SEP 2008
DOI: 10.1002/adfm.200800321
Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Additional Information
How to Cite
Doe, C., Choi, S.-M., Kline, S. R., Jang, H.-S. and Kim, T.-H. (2008), Charged Rod-Like Nanoparticles Assisting Single-Walled Carbon Nanotube Dispersion in Water. Advanced Functional Materials, 18: 2685–2691. doi: 10.1002/adfm.200800321
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Publication History
- Issue published online: 16 SEP 2008
- Article first published online: 1 SEP 2008
- Manuscript Revised: 3 MAY 2008
- Manuscript Received: 3 MAR 2008
Keywords:
- neutron scattering;
- rod-like nanoparticles;
- single-walled carbon nanotubes;
- solution processing
Graphical Abstract
A new dispersant, charged rod-like nanoparticle (cROD), which simultaneously utilizes three different dispersion mechanisms including surfactant adsorption, polymer wrapping, and charge repulsion to synergistically enhance the dispersion of SWNTs in water has been demonstrated. Simultaneous application of the three different dispersion mechanisms is achieved by using polymerized charged rod-like nanoparticles which have hydrophobic cores surrounded by hydrophilic surfaces with controlled surface charge densities. (see figure).
Abstract
A new dispersant for stabilization of single wall carbon nanotubes (SWNTs) in water that simultaneously utilizes three different dispersion or stabilization mechanisms: surfactant adsorption, polymeric wrapping, and Coulomb repulsive interaction, has been demonstrated. The new dispersant, a charged rod-like nanoparticle (cROD), is a cylindrical micelle wrapped by negatively charged polymers which is fabricated by the aqueous free radical polymerization of a polymerizable cationic surfactant, cetyltrimethylammonium 4-vinylbenzoate (CTVB), in the presence of sodium 4-styrenesulfonate (NaSS). The surface charge density of the cRODs is controlled by varying the concentration of NaSS. Dispersions of SWNTs are obtained by sonicating a mixture of SWNTs and cROD in water, followed by ultra-centrifugation and decanting. While the cRODs with neutral or low surface change densities (0 and 5 mol % NaSS) result in very low dispersion power and poor stability, the cRODs with high surface charge densities (15, 25, and 40 mol % NaSS) produce excellent dispersions with SWNT concentration as high as 437 mg L−1 and long term stability. The sharp van Hove transition peaks of the cROD assisted SWNT dispersions indicate the presence of individually isolated SWNTs. Atomic force microscopy and small angle neutron scattering analysis show that the dominant encapsulation structure of the cROD assisted SWNTs is surfactant assisted polymeric wrapping. SWNTs dispersed by the cRODs can be fully dried and easily re-dispersed in water, providing enhanced processibility of SWNTs.