Synergistic Assembly of Single‐Crystal 2D Porphyrin‐Based Organic Polymers via Dative B─N Bonds and Halogen Bonds

Abstract The rigorous synthetic methodologies have significantly impeded the progress in developing single‐crystal extended organic polymers. Notably, the existence of macroscopic single‐crystalline 2D porphyrin‐based organic polymers has never been documented in the literature until now. In this study, we present a groundbreaking example of single‐crystal 2D porphyrin‐based organic polymers that are compatible with single‐crystal X‐ray diffraction (SXRD) for precise structural elucidation. Their formation is fundamentally dependent on the synergistic assembly facilitated by dative B─N bonds and halogen bonds. These crystals exhibit remarkable stability in both air and aqueous environments. Notably, the formation of the B–N Lewis pairs within these crystals significantly enhances the separation of photogenerated carriers, and their single crystals demonstrate exceptional photocatalytic activity for the production of hydrogen peroxide (H 2 O 2 ) from water and oxygen, without the requirement for sacrificial agents. This pioneering discovery establishes a new approach for crystalline control within the realm of organic polymers.