When adsorption and desorption are the only electrode processes on an electrode, the voltammetry curves are symmetric to the potential axis and the charge vs. potential curve exhibits no hysteresis, provided that the sweeprate and adsorbate concentration are sufficiently small and large, respectively. If the latter conditions do not hold, the adsorption process becomes diffusion-controlled, and the voltammograms become asymmetric. Assuming Langmuirian adsorption, a procedure employing a combination of integration and semiintegration of the measured current is suggested by which the effect of diffusion can be removed from the measured voltammograms. The procedure is supported by numerical simulations.
Print ISSN: 0942-9352
Volume: 221, 09/2007
Pages: 1137 - 1147