CeO₂-Based Electrocatalysts for the Oxygen Evolution Reaction: Design, Dynamic Mechanisms, and Electrolyte...

CeO₂-based electrocatalysts are promising for the oxygen evolution reaction (OER) owing to their distinctive Ce³⁺/Ce⁴⁺ redox flexibility, large oxygen-storage capacity, and lattice adaptability. More importantly, CeO₂ can dynamically regulate catalyst surface reconstruction and electronic structure while significantly enhancing catalytic activity and long-term stability. In this review, we first focus on CeO₂-based electrocatalysts for OER from structural characteristics, design principles and strategies, structure-property relationships, interfacial structure, as well as critical evaluation of design strategies and selection principles. The mechanistic roles of CeO₂ in OER are highlighted, including redox chemistry and oxygen-vacancy (O_v) dynamics, electronic-structure modulation and charge transfer, interfacial coupling and surface reconstruction, as well as operando evidence and the controversy over lattice-oxygen participation. The performance of CeO₂-based OER electrocatalysts in different electrolytes, including alkaline, acidic, and seawater media, is also summarized to demonstrate their applicability under diverse operating conditions. Finally, from the perspectives of electronic-structure evolution, redox-state transitions, lattice evolution, and catalytic pathways, this review summarizes the underlying mechanisms by which CeO₂ regulates the dynamic catalytic behavior of OER and provides an outlook on future design strategies for developing highly efficient and durable CeO₂-based electrocatalysts.