Vinyl-Group-Anchored Covalent Organic Framework for Promoting the Photocatalytic Generation of Hydrogen Peroxide

The artificial photosynthesis of H₂O₂ from water and oxygen using semiconductor photocatalysts is attracting increasing levels of attention owing to its green, environmentally friendly, and energy-saving characteristics. Although covalent organic frameworks (COFs) are promising materials for promoting photocatalytic H₂O₂ production owing to their structural and functional diversity, they typically suffer from low charge-generation and -transfer efficiencies as well as rapid charge recombination, which restricts their use as catalysts for photocatalytic H₂O₂ production. Herein, we report a strategy for anchoring vinyl moieties to a COF skeleton to facilitate charge separation and migration, thereby promoting photocatalytic H₂O₂ generation. This vinyl-group-bearing COF photocatalyst exhibits a H₂O₂-production rate of 84.5 μmol h^-1 (per 10 mg), which is ten-times higher than that of the analog devoid of vinyl functionality and superior to most reported COF photocatalysts. Both experimental and theoretical studies provide deep insight into the origin of the improved photocatalytic performance. These findings are expected to facilitate the rational design and modification of organic semiconductors for use in photocatalytic applications.