Surface state and intermediates in the oxygen evolution reaction with ultrathin electrodes

The oxygen-evolution reaction (OER) is a slow reaction that needs to be catalyzed in order to proceed at rates appropriate for industrial hydrogen production. Frequently observed deviations at high potentials from the classical Tafel relation between current and potential are currently not well understood but are significant for the understanding of the mechanism of the OER. XANES/EXAFS of the Ni, Fe, and Co-edges in ultrathin metal films are expected to provide information on oxidation states and bond lengths of the electrochemical interface that can be interpreted in terms of the adsorbed intermediates of the OER. We therefore propose here to record such data in situ in an electrochemical cell and combine the results with an analysis of the OER that also involves microkinetic modeling and in-situ Raman spectroscopy of the same electrodes.