Donor–Acceptor Type Hypercrosslinked Organic Polymers for Highly Efficient Photosynthesis of H ₂ O ₂

Artificial photosynthesis for photocatalytic H 2 O 2 synthesis has emerged as a highly promising sustainable alternative. Donor–acceptor (D–A) organic polymers stand out among catalytic materials due to their exceptional structural tunability and environmental benignity—key advantages for practical applications. However, integrating D–A motifs into π‐conjugated frameworks (e.g., conjugated microporous polymers, CMPs) often alters the photoelectrochemical properties of the monomers through strong π–π interactions and extended conjugation, limiting catalytic performance. Herein, 1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN)‐based donor–acceptor (D–A) hypercrosslinked organic polymer (HOP) are reported, synthesized via Friedel‐Crafts alkylation with dimethoxymethane (DMM) as the crosslinker. The optimal 4CzIPN‐based HOP (DMM‐15) achieves a H 2 O 2 production rate of 2.31 mmol g − 1 h − 1 in pure water (≈12.8‐fold higher than Scholl‐coupled 4CzIPN‐CMPs) and also performs well under outdoor sunlight. Mechanistic studies reveal DMM‐introduced ─OCH 3 enhances hydrophilicity and optimize electronic structure, thereby favoring the two‐electron ORR pathway for efficient H 2 O 2 generation. This work provides a new design paradigm for artificial photosynthesis materials.