Advancing Bifunctional Photocatalysis With COF-Based Materials: Synergistic H₂O₂ Production and In Situ Utilization.

The photocatalytic generation of hydrogen peroxide (H₂O₂) represents a sustainable methodology for producing this essential oxidant, potentially offering a viable alternative to the energy-intensive anthraquinone process. Among various candidates, covalent organic frameworks (COFs) have emerged as exceptional photocatalysts owing to their modularly adjustable porous structures, customizable electronic properties, and superior charge-carrier mobility. In the past years, advancements in COF-based materials have demonstrated significant progress in the photocatalytic synthesis of H₂O₂, particularly as the structural customizability of COFs provides an optimal platform for achieving high selectivity and efficiency in two-electron oxygen reduction reactions (ORRs) and water oxidation reactions. Building on these advantages, recent research has gradually evolved from the isolated generation of H₂O₂ to the development of integrated bifunctional systems that utilize H₂O₂ in situ for synergistic applications. This mini-review aims to encapsulate the recent advancements in COF-based materials-mediated dual-function photocatalysis, which couples H₂O₂ production with processes such as pollutant degradation, uranium extraction, organic synthesis, and hydrogen evolution. It examines the rational design strategies and reaction mechanisms of these bifunctional COFs and discusses the prevailing challenges and future research directions.