Redox‐Mediated TEMPO‐Based Donor‐Acceptor Covalent Organic Framework for Efficient Photo‐Induced Hydrogen Peroxide Generation

Abstract Molecular engineering of covalent organic frameworks (COFs) offers an alternative approach to conventional anthraquinone oxidation via photo‐induced H 2 O 2 production from O 2 reduction. Despite their potential, reported photocatalysts suffer limited proton mobility, low selectivity, and insufficient charge separation and utilization. Herein, we report a nitroxyl radical (TEMPO) decorated two‐dimensional (2D) donor‐acceptor (D‐A)‐COF photocatalyst via a one‐pot strategy. Under visible light irradiation, highly crystalline TAPP‐TPDA‐TEMPO‐COF ( TT‐T‐COF ) exhibits a remarkable photocatalytic H 2 O 2 yield of 10066 μmol g −1 h −1 in two‐phase water‐benzyl alcohol (10 % BA) system through direct two‐electron (2 e − ) pathway. The mechanistic study by DFT calculations and in situ DRIFT spectra suggests Yeager‐type adsorption of *O 2 ⋅ − intermediate on the nitroxyl radical site (N−O⋅). The efficient photocatalytic performance and stability of TT‐T‐COF are attributed to the involvement of the nitroxyl radical, which enhances selective O 2 adsorption, establishes a distinct electron density distribution, and facilitates photogenerated charge separation compared to TT‐HT‐COF and TT‐COF counterparts. This study uncovers a new perspective for constructing metal‐free, redox‐mediated radical‐based COFs for sustainable energy conversion, storage, and biomedical applications.