Fundamentals of surface reconstruction and its interplay with oxygen evolution reaction: Insights from spinel oxides

The alkaline oxygen evolution reaction (OER) serves as a critical half-reaction in numerous energy conversion and storage devices. However, its sluggish four proton-electron transfer process severely limits the overall efficiency of these devices, underscoring the urgent need to develop high-performance OER catalysts. A growing consensus has emerged that the catalytically active species is often not the initially designed structure, but rather an active phase formed through surface reconstruction. Therefore, researchers should look beyond the design of the initial structure and focus instead on investigating the surface reconstruction process. In this review, we will systematically summarize the definition, phenomena, influence, and triggering methods of surface reconstruction through spinel oxides. Spinel oxides are ideal candidates for mechanistic studies because their diverse coordination structures allow modification at tetrahedral or octahedral sites, which can significantly tune intermediate conversion kinetics, surface reconstruction, and catalytic performance. Finally, as a key focus, we will analyze the interplay between surface reconstruction and OER, which has not been covered in current published reviews. Based on extensive research on spinel oxides, we conclude that the conversion of OER intermediates may ultimately determine surface reconstruction.