Ionic pair-engineered amino acid organic frameworks for synergistic CO2 capture and conversion

In addressing the critical challenge of achieving functional synergy in sustainable materials, this study introduces an innovative ionic-pair strategy to construct amino acid-derived green organic polymer frameworks with specifically tailored active sites for CO 2 adsorption and conversion, devoid of halide anions and metal ions. The intrinsic properties and microstructure of these polymers were meticulously modulated through ionic-pairing between amino acid monomers. Comprehensive characterizations and molecular dynamic simulations systematically verified the presence of dual-active sites and stability of the architecture. Experimental and kinetic analyses indicate that these polymers exhibit exceptional performance in CO 2 adsorption capacity and catalytic conversion, with an activated energy of 15.76 kcal·mol −1 . Furthermore, the adsorption and catalytic mechanisms were extensively investigated using the Monte Carlo method and density functional theory calculations. The amino group in AMA-Glu effectively adsorbs and activates CO 2 , while epoxides undergo nucleophilic attack by the carboxylate anion, facilitating ring-opening reactions. The synergistic interaction between the two groups promotes the cycloaddition reaction. Under conditions devoid of co-catalyst, solvent, and halogen at 80 °C for 8 h, the yield of cyclic carbonates achieved 94.3 %, demonstrating strong competitive performance. This study offers substantial theoretical and practical insights into the utilization of green organic catalytic materials for CO 2 conversion.