title: Highly efficient exfoliation of individual single-walled carbon nanotubes by biocompatible phenoxylated dextran.
abstract: Highly efficient exfoliation of individual single-walled carbon nanotubes (SWNTs) was successfully demonstrated by utilizing biocompatible phenoxylated dextran, a kind of polysaccharide, as a SWNT dispersion agent. Phenoxylated dextran shows greater ability in producing individual SWNTs from raw materials than any other dispersing agent, including anionic surfactants and another polysaccharide. Furthermore, with this novel polymer, SWNT bundles or impurities present in raw materials are removed under much milder processing conditions compared to those of ultra-centrifugation procedures. There exists an optimal composition of phenoxy groups (∼13.6 wt%) that leads to the production of high-quality SWNT suspensions, as confirmed by UV-vis-nIR absorption and nIR fluorescence spectroscopy. Furthermore, phenoxylated dextran strongly adsorbs onto SWNTs, enabling SWNT fluorescence even in solid-state films in which metallic SWNTs co-exist. By bypassing ultra-centrifugation, this low-energy dispersion scheme can potentially be scaled up to industrial production levels.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Taeyun
authors.initials: T
authors.lastname: Kwon
authors.forename: Gyudo
authors.initials: G
authors.lastname: Lee
authors.forename: Hyerim
authors.initials: H
authors.lastname: Choi
authors.forename: Michael S
authors.initials: MS
authors.lastname: Strano
authors.forename: Woo-Jae
authors.initials: WJ
authors.lastname: Kim
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D003911:Dextrans / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D001672:Biocompatible Materials; D003911:Dextrans; D037742:Nanotubes, Carbon