THE OSCILLATORY ELECTRODISSOLUTION OF COPPER IN ACIDIC CHLORIDE SOLUTION .1. 0.1M CHLORIDE

The electrodissolution of copper in solutions of 1N H2SO4 and 0.1M NaCl is studied. Results were obtained under potentiostatic conditions with a rotating disk anode at 200 and 1000 rpm over the potential range 100–1100 mV vs. a saturated calomel electrode. Potentiostatic current oscillations were observed for 300 mV ≤ E ≤ 1050 mV at 1000 rpm while oscillations were observed for 275 mV ≤ E ≤ 650 mV at 200 rpm. We describe the general changes in electrode surface morphology and in the film which covers the electrode surface during the course of the experiments, which exhibit oscillatory behavior, and we relate the nature of the film and surface morphology to the characteristics of the current oscillations. Some general conclusions are drawn about the features of this oscillatory system including the role of mass transfer and electrochemical reaction. © 1990, The Electrochemical Society, Inc. All rights reserved.