The anodic dissolution of copper was examined in oxygenated sulfuric acid solution. A characteristic property of the anodic process is that the oxidation process Cu → Cu
2+ involves the detectable intermediate Cu
+, which should disproportionate into Cu and Cu
2+ in the thermodynamic equilibrium state. On the other hand, H
2O
2 was formed during anodic dissolution in oxygenated solution by the reaction of Cu
+ with O
2. The intermediate Cu
+ and the byproduct H
2O
2 were detected in this study using a rotating ring-disk electrode. The anodic dissolution process including the role of oxygen was elucidated through the detection of Cu
+ and H
2O
2. The decrease in the activity of Cu
+ in the presence of O
2 involved a negative shift of the partial current of Cu → Cu
2+ (or Cu
+), and resulted in a negative shift of the corrosion potential with increasing stirring rate of the solution. In addition, Cu
+ was found to be not a transient intermediate, but rather, a thermodynamic equilibrium species. The acceleration of the corrosion rate in the presence of O
2 was elucidated successfully to be due to the couple of the partial currents for Cu → Cu
+ and O
2 → H
2O
2.
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