Electronic transitions during plasma electrolytic oxidation of aluminum

In this article, we have presented our recent investigation of electronic transitions originating from barrier anodic oxide films under the conditions of plasma electrolytic oxidation in both organic and inorganic electrolytes. For the first time we have recorded luminescence spectra during electric breakdown and observed several intensive emission band peaks. Analysis based on literature data on atomic species whose presence is possible in this experimental setup showed that luminescence is related to electron transitions in atoms Al, O, H, Na. Furthermore, these results point to the same cause of optical radiation during aluminum anodization in inorganic and organic electrolytes under the breakdown conditions.