Agile Construction of Bioinspired Porous Ionic Hyper-Crosslinked Polymers for Enhanced CO₂ Capture and Conversion

Hydrogen bond interactions between alkaloids in deoxyribonucleic acid (DNA) maintain the stability of the double helix structure. Inspired by this principle, in this work, we present a one-pot synthesis of ionic hyper-cross-linked polymers (iHCPs) via simultaneous quaternization and Friedel-Crafts alkylation reactions of alkaloids and biphenyl dichloride (BP). These iHCPs exhibited hydrogen bonding capabilities, abundant alkaline and ionic active sites, as well as hierarchically porous structures with ultrahigh surface areas (up to 1480 m²·g^-1). The optimized iHCPs, AN-BP(1:3), demonstrated exceptional CO₂ adsorption (154.4 mg·g^-1 at 273 K and 1 bar) and served as a recyclable catalyst for the solvent-free conversion of CO₂ and epoxides into cyclic carbonates without requiring additional cocatalysts. In situ FTIR spectroscopy and density functional theory (DFT) calculations revealed that basic groups enhanced the CO₂ adsorption and facilitated chloride ions in promoting the epoxide ring-opening reaction via hydrogen bonding, thereby reducing the relative Gibbs free energy barrier. This work establishes a bioinspired design paradigm for ionic polymers by integrating pore engineering with hydrogen-bond catalysis, thus advancing both CO₂ capture and conversion.