Donor-acceptor sp² covalent organic frameworks for photocatalytic H₂O₂ production and tandem bisphenol-A degradation

Covalent organic frameworks (COFs) emerge as innovative photocatalysts featuring systematically tuned chemical structures, nano-porosity, and photoelectric properties. We have shown in the last years that COFs are excellent photocatalysts and they are able to produce hydrogen peroxide (H2O2) from oxygen and water. Despite the recent surge in the photosynthesis of H2O2 using COFs, its subsequent application for tandem pollutant remediation as a tangible green alternative to Fenton chemistry has not yet been comprehensively explored. In this study, we synthesized three highly crystalline sp(2 )COFs with different donor-acceptor (D-A) strengths, employing triazine units as the electron acceptor moiety. The D-A alignment promotes photogenerated charge separation, augmenting the photocatalytic process, which resulted in the TMT-TT-COF achieving a H2O2 production rate of 1952 mu mol g(-1) h(-1) without any sacrificial agents. The COFs also manifested a rapid photocatalytic degradation of bisphenol A (BPA) from a variety of real-life waterbodies. This study pioneers the in situ H2O2 production via COFs to subsequently generate other reactive oxygen species (ROS) for direct organic pollutant degradation in the visible region.