A new method for the identification of electrode surface blocking, based on the measured differences of the diffusion limiting current densities in a thin-layer cell and in a cell with rotating-disk electrode is presented. An equation describing the diffusion limiting current density dependence on the inter-electrode distance in a thin-layer cell was derived. Experimental results were obtained from measurements with model electrodes to demonstrate the possibilities for unambiguous identification of surface blocking phenomena. A model electrode, covered with a partially conductive blocking layer was also discussed and the appearance of two diffusion limiting current density levels on the voltantmograms was experimentally verified. (c) 2007 Published by Elsevier Ltd.