Customized Design of Covalent Organic Framework with Asymmetric Dual-Function Hybrid Linkages for Promoting H2O2 Photosynthesis in Air and Water

Efficient sacrificial-agent-free photosynthesis of H₂O₂ from air and water represents the greenest, lowest-cost, most real-time avenue for H₂O₂ production but remains a challenging issue. Here, we show a general and effective approach through a structural design on covalent organic frameworks (COFs) with asymmetric dual-function hybrid linkages for boosting the H₂O₂ photosynthesis of the COFs. Through such design we can equip a COF with not only a catalytic active center but also a special function for isolating the D-A motif, which consequently endows the COF (CI-COF) built on asymmetric dual-function hybrid linkages with a significantly enhanced efficiency in the generation, transmission, and separation of photogenerated carriers, relative to the COF (II-COF and CC-COF) built on symmetric single-function single linkages. Correspondingly, the performance of H₂O₂ photosynthesis is enhanced by three or five times. Accompanied is the largely promoted O₂ utilization and conversion efficiency from 36.6% to 99.9%. A rare dual-channel H₂O₂ photosynthesis is suggested for the CI-COF.