Activation of voltammetric response of two-component film of functionalized fullerenes bearing a redox probe and palladium
|Marta E. Płońska-Brzezińska 1, Krzysztof Winkler 1, Suresh Gadde 2, Francis D. Souza 2, Alan L. Balch 3|
1. University of Białystok, Institute of Chemistry, Hurtowa 1, Białystok 15-399, Poland
Electronically conductive carbon materials are known as effective electrode materials for electronic, electrochemical, and analytical applications. The electronic properties of these materials depend on their oxidation state. Hence, reversible addition and abstraction of electrons, and switching process from a non-conducting to a conducting state are important factors for these materials to be useful. The oxidation or reduction of the material generates electronic conductivity inside the polymeric phase. Different factors, including the degree of solvent swelling, supporting electrolyte, and the structure and morphology of the film are known to affect the process of conductivity switching which also determine the redox properties of the materials.
The electrochemical reduction of a solution containing a fullerene, generally C60, and various transition metal complexes results in the formation of electrochemically active films on the electrode surface. In these films, fullerene moieties are covalently bound to transition metal atoms or their complexes to form a polymeric network. The two-component films, C60/Pd and C60/Pt, prepared from C60 and palladium or platinum containing precursors are particularly interesting. These films can be readily prepared with relatively high yields. They exhibit high electrochemical stability over a large potential range. Electropolymerization of 2-ferrocenylfulleropyrrolidine (Fc-C60/Pd), a fullerene with a covalently appended ferrocene, in the presence of palladium and platinum complexes also produces films.
In this presentation, we report the electrochemical properties of new two-component films formed from a zinc porphyrin appended fullerene and palladium acetate and compare this new type of film with the films formed from C60 and palladium (C60/Pd), 2-ferrocenylfulleropyrrolidine and palladium (Fc-C60/Pd). The redox-active films were formed in solution containing a large excess of the palladium acetate precursor which lead to the deposition of palladium particles onto the growing polymer. These films undergo a significant change in redox activity when polarized at positive potentials.
Presentation: Short communication at SMCBS'2005 Workshop, by Marta E. Płońska-Brzezińska
See On-line Journal of SMCBS'2005 Workshop
Submitted: 2005-07-27 09:17 Revised: 2009-06-07 00:44