Specific potential scan programs have been used to investigate the electro-reduction behaviour of cuprous oxides anodically formed on copper electrodes in concentrated NaOH solutions. The obtained voltammograms exhibit 3 cathodic current peaks. The peak charges are closely related to anodic polarization potential, polarization time and potential scan rate. These cathodic peaks have been semi-quantitatively contrasted with XRD and XPS spectra to identify anodic products reduced under each cathodic peak. A complex model including adsorption-crystallization and dissolution-precipitation mechanisms for the formation of cuprous oxide is proposed.

Key words: COPPER, CATHODE, X-RAY DIFFRACTION ANALYSIS, REDUCTION, X-RAY PHOTOELECTRON SPECTROMETRY, ELECTRODE REACTION