Surface regulation of perovskite oxides with cation preference for efficient trifunctional electrocatalysts

This study presents a straightforward chemical approach to induce cationic surface defects on SrCoO_3-δ (SCO) perovskites by selectively etching a-site Sr elements on the surface. The modified SCO-30 catalyst from this method exhibits an optimized thickness of cobalt-rich amorphous layer enriched with oxygen vacancies. This modification enhances the trifunctional catalytic activity for oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) in an alkaline electrolyte. Importantly, the perovskite's structure remains unchanged during the surface engineering process. These findings underscore cationic defect engineering as an effective strategy for the rational design of high-performance electrocatalysts, showcasing potential applications in diverse electrochemical processes.