Enhanced carbon dioxide diffusion and conversion in cycloaddition reaction of carbon dioxide with terminal epoxides catalyzed by type III porous liquids

Combining the fluidity of ionic liquids (ILs) with the permanent porosity of metal-organic frameworks (MOFs), type III porous liquids (type III-PLs) demonstrate exceptional catalytic activity for CO 2 capture and cycloaddition reactions. The ZIF-8-based type III-PLs (ZIF-8/1-methyl-3-propylimidazolium bromide ([PMIm]Br)) catalysts achieved a 50.39 % increase in CO 2 conversion and a styrene carbonate yield of 93.08 % at 80 °C and 1.0 MPa. DFT calculations revealed a synergistic effect of ZIF-8/[PMIm]Br catalysts: The Zn active sites in ZIF-8 lowered the energy barriers for epoxide ring opening and CO 2 insertion, while [PMIm]Br provided nucleophilic sites to facilitate the reaction. Additionally, molecular dynamics simulations showed enhanced CO 2 diffusion at the gas-liquid interface in the ZIF-8/[PMIm]Br system, accelerating the reaction rate. This study offers theoretical insights for designing more efficient type III-PLs catalysts for the industrial utilization of CO 2 as a C1 resource.