title: Outer wall selectively oxidized, water-soluble double-walled carbon nanotubes.
abstract: The outer walls of double-walled carbon nanotubes (DWNTs) were selectively oxidized using a combination of oleum and nitric acid. Intercalation of oleum between bundled DWNTs enabled a homogeneous reaction by equally exposing all outer wall surfaces to the oxidants. At optimized reaction conditions, this double-wall chemistry enabled high water solubility through carboxylic acid functional groups introduced to the outer wall, while leaving the inner tube intact, as shown by Raman scattering and high resolution TEM. These outer wall selectively oxidized DWNTs retained electrical conductivity up to 65% better than thin films of similarly functionalized single-walled carbon nanotubes, which can be attributed to enhanced electrical percolation via the nonoxidized inner tubes.
authors.affiliation: Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: Alexandra H
authors.initials: AH
authors.lastname: Brozena
authors.forename: Jessica
authors.initials: J
authors.lastname: Moskowitz
authors.forename: Beiyue
authors.initials: B
authors.lastname: Shao
authors.forename: Shunliu
authors.initials: S
authors.lastname: Deng
authors.forename: Hongwei
authors.initials: H
authors.lastname: Liao
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Gaskell
authors.forename: YuHuang
authors.initials: Y
authors.lastname: Wang
mesh_terms: D004560:Electricity; D007700:Kinetics; D055595:Mechanical Phenomena; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D012995:Solubility; D013057:Spectrum Analysis; D013379:Substrate Specificity; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon; D014867:Water