Enhanced Electrocatalysts Fabricated via Quenched Ultrafast Sintering: Physicochemical Properties and Water Oxidation Applications

Abstract The synthesis of transition metal oxides is typically time‐ and energy‐consuming. Recently, fast sintering methods have demonstrated great potential in reducing ceramic sintering time and energy use, improving the commercial prospects of these materials. In this article, a quenched ultrafast high‐temperature sintering (qUHS) technique is developed to sinter metastable brownmillerite SrCoO 2.5 (SCO) in less than a minute. Surprisingly, SCO fabricated by qUHS shows higher activity for the oxygen evolution reaction (OER) than solid‐state‐reaction‐synthesized SCO. Comparing samples produced by these two techniques, the increased OER performance of SCO qUHS is likely due to the synergistic combination of surface Co chemical state, higher mesoporosity, and enhanced hydroxyl ion (OH – ) adsorption. This work demonstrates the potential of qUHS for producing high‐performance electrocatalysts and provides detailed insights into the impact of ultrafast sintering on the materials’ physical properties and electrocatalytic activity.