Relaxation of the adsorption with charge transfer: The iodide ion adsorption on a platinum electrode

The relaxation of the iodide ion adsorption on platinum electrodes with smooth and developed surfaces is studied in the time range 10(-4) to 10(3) s and frequency range 10(-3) to 10(5) Hz. Mathematical models matching experimental data to within the experimental accuracy are designed. Most adsorption centers on platinum have relaxation times tau > 0.1 s. The fraction of adsorption centers with tau > 100 s increases on the electrode with the developed surface, and in the ranges t < 0.1 s and F > 2 Hz, characteristics of this electrode are almost completely defined by the surface porosity. It is discovered that the electrode surface becomes smoother, leading to a slow drift of characteristics with time.