Space Charge Effects at Passive Zinc Electrodes

We report on the behavior f zinc electrodes in alkaline solutions saturated with soluble zinc species. It is shown that space charge layer effects occur at the passivated zinc electrodes. By alternative interpretations of impedance dispersion spectra, based on the application f the differential effective medium theory and equivalent circuits, respectively, a con-nection between impedance and morphology is suggested. The study of the electrochemical properties of zinc has begun with electrochemistry itself, and it seems that it will cont inue well into the future. Numerous reviews have been written (1), and recent research trends are pre-sented in Ref. (2). Our interest has been focused on the properties of the passive'zinc electrodes (3-5). In previ-ous papers, we have shown that the differential effective medium theory can appropriately account for the imped-ance of passivated zinc electrodes. In the present paper, we show the existence of space charge effects in passiv