Electrocatalysis in photochemically activated electropolymerized thin films

In reductively electropolymerized thin films of poly-cis-[Ru(vbpy)2(py)2](PF6)2 ("vbpy" is 4-methyl-4'-vinyl-2,2'-bipyridine and "py" is pyridine), on glassy carbon electrodes, photochemical ligand loss with aqueous HClO4 in the external solution occurs to give poly-cis-[Ru(vbpy)2(OH2)2](ClO4)2, but the efficiency of ligand loss is greatly decreased compared to the efficiency in solution. In cyclic voltammograms of films containing the aqua complex, there is evidence for both RuIII/II and higher oxidation state RuIV/III, RuV/IV, and RuVI/V couples. The redox chemistry of the resulting films is dictated by the film structure and can be controlled by varying the electropolymerization conditions and external solution composition. The oxidation of alcohols by these higher oxidation state couples has been investigated electrochemically.