Advancing HO electrosynthesis: enhancing electrochemical systems, unveiling emerging applications, and seizing opportunities.

Hydrogen peroxide (HO) is a highly desired chemical with a wide range of applications. Recent advancements in HO synthesis center on the electrochemical reduction of oxygen, an environmentally friendly approach that facilitates on-site production. To successfully implement practical-scale, highly efficient electrosynthesis of HO, it is critical to meticulously explore both the design of catalytic materials and the engineering of other components of the electrochemical system, as they hold equal importance in this process. Development of promising electrocatalysts with outstanding selectivity and activity is a prerequisite for efficient HO electrosynthesis, while well-configured electrolyzers determine the practical implementation of large-scale HO production. In this review, we systematically summarize fundamental mechanisms and recent achievements in HO electrosynthesis, including electrocatalyst design, electrode optimization, electrolyte engineering, reactor exploration, potential applications, and integrated systems, with an emphasis on active site identification and microenvironment regulation. This review also proposes new insights into the existing challenges and opportunities within this rapidly evolving field, together with perspectives on future development of HO electrosynthesis and its industrial-scale applications.