Functionalization of carbon nanotubes by electrochemical reduction of aryldiazonium salts: A bucky paper electrode

Small-diameter (ca. 0.7 nm) single-wall carbon nanotubes are predicted to d isplay enhanced reactivity relative to larger-diameter nanotubes due to inc reased curvature strain. The derivatization of these small-diameter nanotub es via electrochemical reduction of a variety of aryl diazonium salts is de scribed. The estimated degree of functionalization is as high as one out of every 20 carbons in the nanotubes bearing a functionalized moiety. The fun ctionalizing moieties can be removed by heating in an argon atmosphere. Nan otubes derivatized with a 4-tert-butylbenzene moiety were found to possess significantly improved solubility in organic solvents. Functionalization of the nanotubes with a molecular system that has exhibited switching and mem ory behavior is shown. This represents the marriage of wire-like nanotubes with molecular electronic devices.