Localized Asymmetric Electron Distribution in Covalent Organic Frameworks Promotes Efficient Photocatalytic H2O2 Production

• • Fo-COFs achieve a quantum yield of 8.8% for H2O2 photosynthesis in pure water, demonstrating a significant improvement over symmetric COFs and underscoring the potential for sustainable, metal-free photocatalytic H2O2 generation. • • Asymmetric fluorination (ortho vs. para) creates a discretized electron distribution, enhancing O2 adsorption at imine bonds and lowering the Gibbs free energy barrier for the 2e− ORR pathway, as confirmed by DFT calculations. • • The strategic placement of fluorine atoms delocalizes lone-pair electrons onto adjacent carbons, increasing electron density and facilitating electron transfer into the π* orbital of adsorbed O2, accelerating ·OOH intermediate formation. • • This molecular-level design strategy for COFs provides a blueprint for developing efficient, metal-free polymeric photocatalysts, with potential applications in artificial photosynthesis and environmental remediation.