Transient Response of the System Al/Al2O3/Electrolyte. Part I. Galvanostatic Transients

Abstract

Voltage transients under galvanostatic conditions are investigated for the system Al/Al2O3/electrolyte (glycol–borate) and the results, along with similar results obtained by Dewald for the system Ta/Ta2O5/electrolyte (0.1 N H2SO4), are analyzed according to the dielectric relaxation model due to Dignam. This model accounts for the general form of the transients, but systematic discrepancies are apparent. Modification of the model to include two independent ion-current-driven dielectric relaxation processes gives essentially exact agreement with the data and values for the constants in accord with those obtained earlier from potentiostatic transient measurements.