Electrochemistry of fullerene C60 embedded in Langmuir-Blodgett films of artificial lipids on electrodes

A stable Langmuir monolayer of fullerene C-60 and an artificial lipid was formed at the air-water interface and the monolayer was transferred onto an electrode as a Langmuir-Blodgett (LB) film. Here, we focus on the importance of cationic matrix lipid films to the facile electrochemistry of C-60 embedded in a LB film of cationic lipids on an electrode in aqueous media. The electrochemically generated radical monoanion of C-60 embedded in a film of cationic lipid, tridodecylmethylammonium bromide (1), was stable during continuous potential cycling, while the C-60 radical monoanion became unstable after the generation of C-60(2-) due to the exfoliation of the LB film from the electrode. On the basis of the electrolyte dependence and the charge dependence of the matrix lipids, a possible electron-transfer mechanism for the C-60/artificial lipid LB film-modified electrodes is presented. (c) 2005 Elsevier B.V. All rights reserved.