C2-phenyl-substituted benzimidazolium-based covalent organic framework as efficient catalyst for CO_(2) conversion without solvents,metals,and cocatalysts

Covalent organic frameworks(COFs) are a potential platform for carbon dioxide(CO_(2)) conversion owing to their periodic permanent porosity,adjustable structure,and chemical stability.For good catalytic performance in CO_(2) conversion,collaborative multifunctions should be strategically integrated into the catalytic system design and construction.In this study,a four-in-one high-efficiency catalyst was synthesized and tested for CO_(2) cycloaddition to form cyclic carbonate.The obtained Tp-MPB-BrCOF had a high nitrogen content,which enhanced its CO_(2) affinity through substantial Lewis acid-base or dipole-quadrupole interactions;moreover,the acid(protons transferring from oxygen(–OH) to nitrogen(–NH)),hydrogen bond donor(hydroxyl group),and Br-(nucleophile group) served as three active sites,further improving the catalyst activity.These results provide a basis for designing efficient and stable CO_(2)-conversion catalysts.