Azine-Pyridine Frame Generated Covalent Organic Frameworks and Self-Polymerized Films

Engineering covalent organic frameworks (COFs) into industrializable films with inherent functionalities has remained a major challenge in synthetic chemistry. Here, through developing skeletal azine-pyridine conformation, we present an effectual synthetic frame to convert a family of powdery COFs into self-polymerized COFs films under green and ambient conditions. The active proton tautomerism in our azine-pyridine frame offers a thermochromism, facilitating self-polymerization of large-area COFs films from ca. 10 nm to >30 µm thickness with outstanding chemical stability, industrializable processability, and mechanical strength. More remarkably, our azine-pyridine-based COFs first display various fresh properties, i.e., up to 1913 and 624 mg g⁻¹ reducing capacities on ions of Au³⁺ → Au⁰ and Cr⁶⁺ → Cr³⁺, 99.9% UV-blue light shielding and 97.2% transmissivity of visible lights and 10-fold increase in Zn battery lifetime. We expect that the azine-pyridine synthetic frame will serve as a generalizable route to boost the development of reticular chemistry, environmental science, and nano-electronics.