Preparation and characterization of mixed-valent of ruthenium oxide/hexacyanoferrate/silicomolybdate hybrid films and their electrocatalytic properties

Polynuclear mixed-valent ruthenium oxide/hexacyanoferrate/silicomolybdate (RuO/Fe(CN)63-/SiMo12O404-) have been prepared using repetitive cyclic voltammetry. The ruthenium oxide/hexacyanoferrate (RuO/Fe(CN)63-) and RuO/silicomolybdate (RuO/SiMo12O404-) films have also been prepared using repetitive cyclic voltammetry. The cyclic voltammograms recorded for the deposition of the mixed-valent ruthenium oxide/hexacyanoferrate/silicomolybdate hybrid films directly from the mixing of Ru3+, Fe(CN)63- and SiMo12O404- ions from the acidic aqueous solutions. The polynuclear mixed-valent ruthenium oxide/hexacyanoferrate/silicomolybdate films exhibited five redox couples. The electrochemical quartz crystal microbalance and cyclic voltammetry, were used to study the growth mechanism of the polynuclear mixed-valent films ruthenium oxide/hexacyanoferrate/silicomolybdate films. The scanning electron microscopy has been used to study the surface morphology of above films. Electrocatalytic reactions of dopamine, ascorbic acid, epinephrine, norepinephrine, S2O82-, SO52-, l-cysteine, and IO3- were carried out using the mixed-valent ruthenium oxide/hexacyanoferrate/silicomolybdate films. Simultaneous electrocatalytic oxidation and reduction of NaNO2 by the hybrid films too were investigated.