Comparison of electrochemical properties of two-component C60-Pd polymers formed under electrochemical conditions and by chemical synthesis

The electrochemical behavior of C-60-Pd polymer formed under electrochemical conditions and by the chemical synthesis was examined. In these polymers, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. Both materials deposited at the electrode surface show electrochemical activity at negative potentials due to the reduction of fullerene cage. Electrochemically formed thin polymeric films exhibit much more reversible voltammetric response in comparison to chemically synthesized polymers. The morphology and electrochemical behavior of chemically synthesized C-60-Pd polymer depend on the composition of grown solution. Chemical polymerization results in formation of large, ca. 50 mu m, crystallic superficial structures that are composed of regular spherical particles with a diameter of 150 nm. The capacitance properties of C-60-Pd films were investigated by cyclic voltammetry and faradaic impedance spectroscopy. Specific capacitance of chemically formed films depends on the conditions of film formation. The best capacitance properties was obtained for films containing 1:3 fullerene to Pd molar ratio. For these films, specific capacitance of 35 Fg(-1) was obtained in acetonitrile containing (n-C4H9)(4)NClO4. This value is much lower in comparison to the specific capacitance of electrochemically formed C-60-Pd film.