Two Mechanisms of Cu2O Formation

As mentioned earUer, oxides can be formed on copper electrodes in various ways, and two main mechanisms are worthy of consideration. One of these is simply copper corrosion, which often occurs in Cu(ll)-free naturally aerated solutions. Intermediate Cu+ ions derived from copper oxidation are able to react with OH anions yielding unstable CuOH that, in turn, decomposes into cuprous oxide and water 

Released electrons are usually consumed in the reduction of dissolved oxygen. The rate of such a conjugated process depends on different factors, such as the oxygen concentration, the acidity of the medium, the copper surface state, and so on. Corrosion intensity can be also suppressed by inhibitors. 

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