The experiments were carried out at a motionless and rotating disk electrodes of 4 mm diameter prepared from ë999 silver. A PI-50-1 potentiostat served as the current source both in d. c. and pulsed modes. To assess the quality of surfaces treated, we measured a standard deviation of the Ra profile by using a Kalibr-252 profilograph-profilometer, determined the reflectivity of the surface, and calculated its fractal dimensionality based on a computer-assisted analysis of silver-electrode surface microimages, according to method of [6].