Efficient synthesis of fullerenol in anion form for the preparation of electrodeposited films.

Abstract

The first electrochemical characterization of the much-studied "fullerenols" has been carried out. The fullerenol was prepared by the reaction of C(60) in deoxygenated tetrahydrofuran with an aqueous NaOH solution using sodium zincate as an electrophilic reagent. The obtained fullerenol is not simply polyhydroxylated C(60) but is a structurally and electronically complex C(60) anion with a molecular formula of Na(+) (2)[C(60) (OH)(12)(O)(2)](2-). This negatively charged fullerenol is in the form of a spherical cluster of 50 nm in diameter, and it can migrate in the same solution to an anode surface and be oxidized into the less soluble fullerenol C(60)O(OH)(12), when 10 V is applied to the electroplating bath. A uniform film, with a particle of 50-250 nm in diameter and a thickness of a few 10-100s of nanometers, is obtained by drying the fullerenol covered anode. This is the first time that studies of water-soluble fullerenols acting as anions for electrodeposited film preparation have been reported. The deposition mechanism has been further demonstrated by electrochemical measurements and dissolved oxygen concentration testing to be an oxidation process consisting of two anodic oxygen evolution processes.