Universality in Oxygen Evolution Electrocatalysis on Oxide Surfaces

Trends in electrocatalytic activity of the oxygen evolution reac- tion (OER) are investigated on the basis of a large database of HO* and HOO* adsorption energies on oxide surfaces. The the- oretical overpotential was calculated by applying standard density functional theory in combination with the computa- tional standard hydrogen electrode (SHE) model. We showed that by the discovery of a universal scaling relation betweenthe adsorption energies of HOO* vs HO*, it is possible to ana- lyze the reaction free energy diagrams of all the oxides in a general way. This gave rise to an activity volcano that was the same for a wide variety of oxide catalyst materials and a uni- versal descriptor for the oxygen evolution activity, which sug- gests a fundamental limitation on the maximum oxygen evolu- tion activity of planar oxide catalysts.