Influence of electrode roughness on cyclic voltammetry

Electrodes with rough surfaces are of great practical importance from both applied and fundamental points of view. The diffusion domain approach is used to model cyclic voltammetry at such electrodes. Electrode roughness only has a significant effect on the shape of cyclic voltammograms and peak currents at relatively high values of electrode roughness. To verify the theory two experimental systems were used: TMPD in acetonitrile and Ru(NH3)(6)Cl-3 in aqueous solution. In both cases cyclic voltammograms on the flat and roughened glassy carbon electrodes were in agreement with theory. Even significant surface roughness produced by deliberate polishing or scratching is not sufficient to be distinguished in cyclic voltammetry experiments conducted under the usual conditions.