Electrochemical nanostructuring of fullerene films - spectroscopic evidence for C-60 polymer formation and hydrogenation

摘要

Electrochemical reduction of ordered C-60 fullerene films in aqueous solution was studied by AFM, FTIR and Raman spectroscopy, mass spectrometry and elastic recoil detection analysis. During the irreversible reduction process the film morphology changed from a heteroepitaxial (111) surface to a nanostructured array with clusters of 20 to 50 nm lateral size on average. On the molecular level the initial C-60 underwent electrochemical reactions to form C-60 polymers and hydrogenated C-60. Chemical follow-up reactions of electrochemically formed C-60(-) with water are responsible for the different reduction behaviour of C-60 films in aqueous solution compared to C-60 reduction in organic solvents and to C-60 doping with alkali metals. Based on the spectroscopic analysis a reaction scheme accounting for the chemical processes at the C-60 vertical bar aqueous electrolyte interface is presented.