Where ξ O is the lateral coefficient from the first part of this work. Using this expression with ∆G ‡ ORR (0) = 0.30 eV, gives ∆G ‡ ORR (1.0) = 0.65 eV. This value is in good agreement with the early experimental literature which estimated the oxide-covered barriers to be 0.62, 51 0.76, 52 or 0.87 eV. As previously discussed, depending on the potential U , not all oxide species are site-blocking. However, to avoid additional complexities and assumptions, we opted for a simpler approach and used a constant value of γ = 0.66. We take n equal to 2, as two platinum sites are required for the RDS at high potentials. Finally, in Figure we plot Equation for our chosen values of ∆G ‡ ORR (0) and obtain plausible current densities versus potential curves. Comparison with the existing experimental literature can be made by using the current density value at 0.9 V j(0.9) which has been reported by various studies to be between 0.1 and 0.4 mA/cm 2 for standard Pt/C catalysts. This suggests, by considering Figure that the activation energy of the RDS on the oxide-free catalyst is indeed between 0.25 and 0.35 eV, giving an estimate of the activation barrier on the oxide covered catalyst between 0.6 and 0.7 eV. Considering both reasonable agreements with the existing literature for ∆G ‡ ORR and j(0.9), we argue that our various assumptions made in the kinetic model are justified and lead to a plausible representation of the polarization curve.