Preparing\nRuthenium Complex-Contained DaTp COFs via\nπ–π Interactions for Visible-Light-Driven Photocatalytic\nHydrogen Peroxide Production

Hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) is a crucial\nenergy\ncarrier with growing significance in sustainable energy systems. Covalent\norganic frameworks (COFs) have recently emerged as promising materials\nfor efficient H<sub>2</sub>O<sub>2</sub> photosynthesis, while transition-metal\ncomplexes are recognized for their efficacy as molecular photocatalysts\nin H<sub>2</sub>O<sub>2</sub> production. This study introduces a\nnovel π–π interaction strategy to immobilize ruthenium\ncomplexes into COFs, using DaTp COF as a model system. This approach\nsignificantly enhances the photocatalytic activity for H<sub>2</sub>O<sub>2</sub> production, achieving an initial rate of 3276 μmol\ng<sup>–1</sup> h<sup>–1</sup> without using scavengers\nunder visible-light irradiation (λ > 420 nm). Notably, incorporating\nruthenium complexes optimizes the oxygen reduction reaction pathways,\nshifting from a less efficient four-electron process to a more efficient\ntwo-electron process. Density functional theory calculations further\nreveal that ruthenium complexes not only broaden the light absorption\nspectrum of the COF but also increase water affinity, directly contributing\nto H<sub>2</sub>O<sub>2</sub> generation. These findings offer a strategic\nframework for designing and enhancing COFs in H<sub>2</sub>O<sub>2</sub> photosynthesis applications.