In H 2 -containing 0.01 M KOH (pink curve), the positive current density between 0.05 V and 1.0 V is attributed to the hydrogen oxidation reaction (HOR), which is inhibited in the region of surface Pt oxide formation at around E > 0.95 V. In O 2 -containing 0.01 M KOH (light blue curve) the negative current density at E < ca. 0.95 V is related to the ORR. In H 2 O 2 -containing 0.01 M KOH (orange curve) the negative current density at around E < 0.95 V is related to the hydrogen peroxide reduction reaction (HPRR), and the positive current density at around E > 0.95 V is related to the hydrogen peroxide oxidation reaction (HPOR). In all cases, the ad-/desorption features observed in the CV recorded in N 2saturated 0.01 M KOH (grey curve), overlap with the current density related to the electrocatalytic reactions. In contrast to literature findings, the here reported current densities are low due to limited diffusion of the reactants to the electrode under stagnant electrolyte conditions. Figures and show the CVs from Figs. 2h and l (step C) recorded after aCGDE with and without waiting time, respectively. Similar results are also obtained when a lower voltage is applied between the PWE and the plasma counter electrode (550 V in Fig. ), as well as with and without shielding the plasma counter electrode by a glass tube (Fig. ). In addition, for comparison, a CV recorded in step A (before the aCGDE treatment) is included in black and a CV recorded after 15 min waiting time without applying aCGDE in green.