Perspective on Visualizing Elementary Steps of Oxygen Evolution Catalysis

Scientific Achievement:

The frontier challenge of oxygen evolution catalysis is to extract the molecular details of its elementary steps. We discuss how advances in spectroscopy and theory are allowing for configurations of reaction intermediates to be elucidated.

Significance and Impact:

We advance the perspective that considering how intermediates form at the two ends of the binding energy range of OH*, O* will enable explicit connections between tailored spectroscopic probes (from X-ray to visible to infrared) and advanced calculations to reveal the reaction steps within the OER.

Research Details:

First principles potential–pH diagrams directly connect the intermediate formation at pre-equilibrium (prior to OER) in cyclic voltammetry of (Ru, Ir)O₂ to molecular coverages.  Core-level spectroscopy of the OH*, O* and their coverages is a cutting-edge challenge.

Semiconducting 3d Ti oxides are good candidates for isolating intermediate configurations by photoexcitation (negligible O*, OH* prior to OER). Further, when holes localize to form bulk and surface hole–polarons distinct optical signatures can be matched to first-principles calculations.