title: Water-soluble full-length single-wall carbon nanotube polyelectrolytes: preparation and characterization.
abstract: HiPco single-wall carbon nanotubes (SWNTs) have been noncovalently modified with ionic pyrene and naphthalene derivatives to prepare water-soluble SWNT polyelectrolytes (SWNT-PEs), which are analogous to polyanions and polycations. The modified nanotubes have been characterized with UV-vis-NIR, fluorescence, Raman and X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The nanotube-adsorbate interactions consist of pi-pi stacking interactions between the aromatic core of the adsorbate and the nanotube surface and specific contributions because of the substituents. The interaction between nanotubes and adsorbates also involves charge transfer from adsorbates to SWNTs, and with naphthalene sulfonates the role of a free amino group was important. The ionic surface charge density of the modified SWNTs is constant and probably controlled by electrostatic repulsion between like charges. The linear ionic charge density of the modified SWNTs is similar to that of common highly charged polyelectrolytes.
authors.affiliation: Department of Chemistry, University of Turku, 20014 Turku, Finland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Paloniemi
authors.forename: Timo
authors.initials: T
authors.lastname: Aäritalo
authors.forename: Taina
authors.initials: T
authors.lastname: Laiho
authors.forename: Hanna
authors.initials: H
authors.lastname: Liuke
authors.forename: Natalia
authors.initials: N
authors.lastname: Kocharova
authors.forename: Keijo
authors.initials: K
authors.lastname: Haapakka
authors.forename: Fabio
authors.initials: F
authors.lastname: Terzi
authors.forename: Renato
authors.initials: R
authors.lastname: Seeber
authors.forename: Jukka
authors.initials: J
authors.lastname: Lukkari