UiO-66 based porous ionic liquids achieving high CO2 capture capacity and kinetics

In order to enhance the CO 2 capture performance of ionic liquids, this work synthesized porous ionic liquids (pILs) utilizing UiO-66 as the porous material and [DMIM][NTf 2 ] as a sterically hindered solvent. By controlling the MOF proportion within a low range (<2.0%), the pILs achieved a dual enhancement in both CO 2 solubility and diffusion coefficient. Comprehensive characterization confirmed the structural integrity, well-defined morphology, and correct chemical composition of the synthesized materials. The CO 2 solubility in the low-pressure region was measured by the isochoric saturation method, and the corresponding diffusion coefficients were calculated based on the semi-infinite volume model. The results demonstrated that the pILs achieved dual enhancement in both CO 2 solubility and diffusion coefficient exhibiting an increase of approximately 20% for both parameters. And the absorption-desorption experiment further showed an enhancement in CO 2 solubility, with over 94% cyclic efficiency after five cycles for the three representative absorption pressure. These results indicate the significant enhancement and exceptional absorption stability of pILs across a wide pressure range. The dual enhancement effect demonstrates the exceptional CO 2 capture performance offering important insights for the practical industrial application.