To explain our findings in the +0.5V bias regime, i.e., the formation of a new oxidation peak following irradiation, we should also refer to the charge transfer at the electrode/electrolyte interface as a reaction rate-limiting process (Figure ). Unlike the behavior of the cell in the negative bias regime, in the positive one, the negatively charged photoacid is attracted to the positively charged anode. Upon light irradiation and the formation of an RO -••• H + ion pair, the RO -anions are now attracted to the positively charged anode and can undergo oxidation, resulting in an increase in the anodic current. To support this hypothesis regarding the positive (+0.5V) regime, we conducted a control experiment where the electrolyte without the PA was titrated with the addition of RO -(from an alkaline condition) during the CA measurement, which resulted in an increase of the current density (Figure and text within).