We successfully described the electrochemical phenomena of potential shifts in cyclic voltammograms, which occur atnanostructured platinum electrodes. It was shown that surface reactions on these high surface area electrodes alter the pH-value of neutral electrolytes in direct proximity of the electrode. These shifts of the potential were described by the strong release and binding of protons, respectively. In the forward scan (release of protons) the electrolyte was acidified, and accordingly alkalized in the backward scan. Further, this led to expansion of the potential range (water window) from 1.4 V to 2 V. We assume that these
effects are independent of the electrode material used and are only dependent on the electrochemically active surface.