Bisite Sulfonate‐Functionalized Covalent Organic Frameworks with Efficient and Dynamic Proton Transportation for Accelerating H ₂ O ₂ Photosynthesis

Abstract Photocatalytic hydrogen peroxide (H ₂ O ₂ ) production using covalent organic frameworks (COFs) relies on the concerted operation of two half‐reactions: oxygen reduction (ORR) and water oxidation (WOR). A critical limitation arises from the frequent proton and O ₂ supply‐demand imbalance between these processes, which constrains overall H ₂ O ₂ yields. To address this challenge, a bisite sulfonate‐functionalized COF (2‐SO ₃ H‐COF) is developed that serves as an efficient proton mediator, promoting both solution‐phase proton/O ₂ uptake and rapid intraframework proton transport through hopping mechanisms. The optimized material demonstrates remarkable performance, yielding 4744 µmol g ⁻¹ h ⁻¹ H ₂ O ₂ under acidic conditions (pH = 1) and even achieving 11 470 µmol g ⁻¹ h ⁻¹ in 10% benzyl alcohol solution, which represents a 3.36‐fold enhancement over unmodified COFs in deionized water. Isotopic labeling and computational studies elucidate how ‐SO ₃ H groups facilitate proton conduction from water into the framework while enhancing O ₂ adsorption, thereby promoting a direct 2e ⁻ ORR pathway. When implemented in a flow reactor system, 2‐SO ₃ H‐COF enables continuous H ₂ O ₂ production while simultaneously degrading >95% of organic dyes and maintaining 99% antibacterial efficacy. These findings establish a general design principle for proton‐regulating photocatalysts and expand the potential of COF materials for sustainable chemistry and environmental applications.