Electrochemical redox processes of fullerene C60 and decamethylferrocene dissolved in cast 1,2-dichlorobenzene film in contact with aqueous electrolyte

Electrochemical processes of fullerene C-60 and decamethylferrocene dissolved in 1,2-dichlorobenzene, supported by tetrahexylammonium perchlorate, film deposited on glassy carbon electrode in contact with aqueous electrolyte was studied by cyclic voltammetry and differential pulse voltammetry. The electrode modified with decamethylferrocene solution exhibits anion sensitive reversible voltammetry resulting from one electron oxidation of the redox probe followed by anion insertion into organic phase. In the presence of more hydrophilic anions like SCN-, NO3-, Br-, Cl- and F- the gradual change from anion insertion to decamethylferrocenium cation expulsion pathway is observed. The voltammetry of fullerene C-60 shows three consecutive reduction-oxidation steps and is also anion sensitive. This effect is less pronounced when fulleride anion with more negative charge is formed. It is proposed that anion sensitivity reflects anion partitioning in supported organic liquid. As proved by ion association study in bulk 1,2-dichlorobenzene subsequent electroreduction of C-60 results in formation of C-60(-), C-60(2-) and C-60(3-) with two, four and six tetrahexylammonium cations respectively. Every of these steps is followed by electrolyte anion expulsion into aqueous phase. As charge of the formed fulleride anion increases the gradual change from anion expulsion to cation insertion mechanism is suggested. (C) 2010 Elsevier B.V. All rights reserved.