title: Giant cationic polyelectrolytes generated via electrochemical oxidation of single-walled carbon nanotubes.
abstract: Previously, reduced single-walled carbon nanotube anions have been used for effective processing and functionalization. Here we report individually separate and distinct (that is, discrete) single-walled carbon nanotube cations, directly generated from a pure anode using a non-aqueous electrochemical technique. Cyclic voltammetry provides evidence for the reversibility of this nanoion electrochemisty, and can be related to the complex electronic density of states of the single-walled carbon nanotubes. Fixed potentiostatic oxidation allows spontaneous dissolution of nanotube cations ('nanotubium'); Raman spectroscopy and transmission electron microscopy show that sequential fractions are purified, separating amorphous carbon and short, defective single-walled carbon nanotubes, initially. The preparation of nanotubium, in principle, enables a new family of nucleophilic grafting reactions for single-walled carbon nanotubes, exploited here, to assemble nanotubes on amine-modified Si surfaces. Other nanoparticle polyelectrolyte cations may be anticipated.
authors.affiliation: Department of Chemistry, Imperial College London, London SW7 2AZ, UK.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Hodge
authors.forename: Mustafa K
authors.initials: MK
authors.lastname: Bayazit
authors.forename: Hui Huang
authors.initials: HH
authors.lastname: Tay
authors.forename: Milo S P
authors.initials: MS
authors.lastname: Shaffer