Recent Advances in Design of Heterogeneous Electrocatalyst for Direct Olefin Epoxidation with Water as the Oxygen Source

Olefin epoxidation is a critically important industrial transformation. However, conventional methods rely on fossil‐derived energy, hazardous oxidants, and harsh reaction conditions. Direct electrochemical olefin epoxidation using water as the oxygen source offers a sustainable alternative, enabling the use of renewable electricity without generating waste. This review provides a comprehensive overview of recent advances in heterogeneous electrocatalysts for the direct epoxidation of olefins with water. Key catalyst design strategies are highlighted, including crystal facet modulation, oxidation state regulation, alloying, single‐atom anchoring, doping, surface modification, and hydrophilicity engineering. Mechanistic insights into reactive oxygen species generation, competition with the oxygen evolution reaction (OER), and catalyst stability are examined, with an emphasis on findings from advanced in situ characterization techniques. Persistent challenges, including poor reactivity of aliphatic olefins, competing OER, and scalability limitations, are critically assessed. Future directions are proposed, focusing on operando characterization, rational catalyst design guided by structure–activity relationships, photoelectrochemical systems, and the development of industrial‐scale electrolyzers. This review aims to provide a roadmap for designing next‐generation electrocatalysts and advancing sustainable epoxidation technologies aligned with green chemistry principles and renewable energy integration.