Silver Oxyfluoride Modified Silver Electrode: Application for Electrocatalytic Oxidation of Methanol

Silver oxyfluoride modified silver electrode was prepared and used to electrocatalytic oxidation of methanol. Fluoride can form a complex with silver ion, and thus be used to modify a silver electrode surface. The electrocatalytic activity of the modified electrode for the oxidation of methanol, in aqueous basic solution was studied by using cyclic voltammetry. Results showed that, silver oxyfluoride modified electrode can improve the activity of Ag towards the oxidation of this small organic molecule. The exchange current density (j0) were 20.37, 10.38 and 1.61 folds higher than for that of bare silver electrode respectively for silver oxyfluoride, silver oxychloride and silver oxybromide modified silver electrodes.The modified electrode showed a stable and linear response in the concentration range of 5×10-3 to 5×10-2 mol L-1 with a correlation coefficient of 0.9953. For silver oxyfluoride modified silver electrode, the transfer coefficient (α), the number of electrons involved in the rate-determining step (nα) and the catalytic rate constant (k) for modified electrode were calculated as 0.45,1 and1.113×105 cm3 mol–1 s–1 respectively.