Thus, even though the thermodynamic descriptor (OH binding energy) predicts OHNafion as a more reactive intermediate, its desorption is hampered by the high kinetic barrier. The Pt(111) surface was reported to be mostly covered by the adsorbed oxygen species at the onset potential of the ORR (0.95 V) and the main surface adsorbates gradually changed from *O into *OH with the decreasing applied potential . These experimental evidence points to the key role of both *O and *OH as reaction intermediates of the ORR at the potential of interest, i.e., 0.9 V. Therefore, the overall ORR activity is likely limited by the kinetics of the following two elementary steps 52 : * 𝑂 + 𝐻 5 + 𝑒 → * 𝑂𝐻 (8) * 𝑂𝐻 + 𝐻 5 + 𝑒 → 𝐻 = 𝑂