Optical spectroscopic studies of dispersion and processing of aqueous inks of single-wall carbon nanotubes Auteur(s): Torres-Canas F. J., Blanc C., Zamora-Ledezma C., Silva Pedro, Anglaret E.
Conference: GDR-I Graphene and Nanotubes, 2015 Annual Meeting (Aussois, FR, 2015-11-29) Ref HAL: hal-01284328_v1 Exporter : BibTex | endNote Résumé: Strategic approaches for dispersing and/or orienting SWNT in films and composites are essential for controling and optimizing their properties [1,2]. Dispersion in a liquid phase is the most efficient way to exfoliate the bundles into individual SWNT. Additives, most often surfactants, have to be used because of the poor solubility of SWNT in all solvents. However, the presence of surfactants in the final films/composites can drastically change their properties. In this talk, we show that a simple dialysis process opens a new route for stabilizing aqueous inks with high concentrations of individual SWNT without surfactant, and for preparing surfactant-free polymer-based composites [3]. Coupled Raman/ photoluminescence spectroscopy studies allow to probe in situ both the dispersion of the nanotubes and the nature of the molecules adsorbed on their surface. We demonstrate a spontaneous exchange between surfactant molecules (bile salts) and polyvinyl alcohol (PVA) chains at the surface of the nanotubes, and a forced exchange by dialysis for both PVA and polyvinyl pyrrolidone (PVP) [3]. |