Benzotrifuran‐based Covalent Organic Frameworks for Artificial Photosynthesis of H2O2 from H2O, O2 and Sunlight

Abstract

Hydrogen peroxide (H2O2) is an important green chemical and a potential energy carrier. Artificial photosynthesis of H2O2 from only H2O and O2 under sunlight is a fascinating and sustainable tactic. However, deficient proton sources come from the kinetically sluggish H2O oxidation process (~s) seriously impede half‐reaction of O2 reduction (μs~ms), leading to inferior photocatalytic efficiency. Herein, we prepare a benzotrifuran‐based covalent organic framework featuring electron donor‐acceptor character with hydrazone linkage. Spatially separated donor‐acceptor π‐stacking columns offer rich O2 reduction and H2O oxidation active sites, also serve as channels for photoinduced charge separation and transport. Importantly, the one‐dimensional pore containing abundant heteroatoms facilitates H2O delivery to oxidation sites and reduces reaction energy barrier, thus improving the kinetic of H2O oxidation. Accordingly, this porous framework achieves efficient H2O2 photocatalysis with an average mass rate of up to 6432 µmol g−1 h−1 from H2O and O2 in the absence of any sacrificial reagent under simulated sunlight by balancing O2 reduction and H2O oxidation reactions.