A New Type of Scaling Relations to Assess the Accuracy of Computational Predictions of Catalytic Activities Applied to the Oxygen Evolution Reaction

Abstract Experimentally, it is well known that the overpotentials for the oxygen evolution reaction (OER) on RuO 2 and IrO 2 are similar and rather low. The question is whether widespread computational electrochemistry models based on adsorption thermodynamics are capable of reproducing such observations. Making use of DFT results of revised Perdew–Burke–Ernzerhof (RPBE) and Perdew–Burke–Ernzerhof (PBE) functionals from six different codes and various types of pseudopotentials, we show that whereas IrO 2 is consistently predicted to have low overpotentials, RuO 2 is predicted to have large overpotentials. A new methodology based on adsorption‐energy scaling relations shows that the inaccurate prediction for RuO 2 stems from its anomalous adsorption energies of oxygen/oxygenates. Including explicit water solvation and using functionals that account for van der Waals interactions such as vdW‐DF, vdW‐DF2 and optPBE‐vdW modifies appropriately the adsorption energies so that both oxides are predicted to be highly active.