Selective CO₂ Adsorption in a Supramolecular Organic Framework

Abstract

Abstract Considering the rapidly rising CO 2 level, there is a constant need for versatile materials which can selectively adsorb CO 2 at low cost. The quest for efficient sorptive materials is still on since the practical applications of conventional porous materials possess certain limitations. In that context, we designed, synthesized, and characterized two novel supramolecular organic frameworks based on C ‐pentylpyrogallol[4]arene (PgC 5 ) with spacer molecules, such as 4,4′‐bipyridine (bpy). Highly optimized and symmetric intermolecular hydrogen‐bonding interactions between the main building blocks and comparatively weak van der Waals interactions between solvent molecules and PgC 5 leads to the formation of robust extended frameworks, which withstand solvent evacuation from the crystal lattice. The evacuated framework shows excellent affinity for carbon dioxide over nitrogen and adsorbs ca. 3 wt % of CO 2 at ambient temperature and pressure.