Hydrogenation of Mixed Ir-Ti Oxide, a Powerful Concept to Promote the Oxygen Evolution Reaction in Acidic Water Electrolysis

A novel and simple strategy of catalytic promotion is presented that is able to significantly improve the oxygen evolution reaction (OER) activity of phase-pure Ir0.30Ti0.7O2 by hydrogen incorporation of 26 at% into Ir0.30Ti0.7O2 through H2 exposure at 150 °C without compromising the long-term stability in acidic water electrolysis. The most attractive feature of hydrogen promotion is the prospect of improving oxidation catalysis for an entire class of materials, namely mixed oxides, and for various oxidation reactions, regardless whether they belong to thermal- or to electrocatalysis.