Binding of pentachloroiridite to plasma polymerized vinylpyridine films and electrocatalytic oxidation of ascorbic acid

Coordination of [IrCl5 (acetonato)) 2- in acetone/methylene chloride to a film of vinylpyridine RF plasma polymerized on a carbon electrode results in an electrode surface wave at +0,40 volt vs. S.C.E. in 1 M H2SO4 . This potential is more negative than expected for -PylrCl5 2- coordination. Charge transport in the film is very fast and the film catalyzes the oxidation of ascorbic acid at a diffusion controlled rate. The film electrochemistry is sensitive to the choice of supporting electrolyte cation but not anion