Quaternary D‐π‐A Covalent Organic Frameworks for High‐Performance H ₂ O ₂ Photosynthesis

Abstract The development of multicomponent covalent organic frameworks (COFs) photocatalysts capable of overcoming limitations in photogenerated charge carrier mobility and suppressing charge recombination remains a significant challenge. Herein, a series of quaternary donor‐π‐bridge‐acceptor (D‐π‐A) COFs with quinoline‐based π bridges are constructed for efficient photocatalytic hydrogen peroxide (H 2 O 2 ) production. Through a multicomponent assembly strategy integrating Schiff base, Povarov, and Doebner reactions, the resulting COFs exhibited enhanced light absorption, optimized band structures, and superior charge separation efficiency. Impressively, COF‐ABC1D2 achieved an excellent photocatalytic H 2 O 2 production rate as high as 5 836 µmol g −1 h −1 in pure water condition, outperforming its ternary and binary counterparts by 3‐fold and 8‐fold, respectively. Comprehensive mechanistic investigations revealed that the quinoline π bridges not only reduce exciton binding energy but also promote directional charge transfer and facilitate a two‐electron oxygen reduction pathway for H 2 O 2 production. This work establishes a new paradigm for designing high‐performance multicomponent COFs for sustainable photocatalysts.