Harnessing the Hybridization of a Metal‐Organic Framework and Superbase‐Derived Ionic Liquid for High‐Performance Direct Air Capture of CO2

Abstract Direct air capture (DAC) of CO 2 has emerged as the most promising “negative carbon emission” technologies. Despite being state‐of‐the‐art, sorbents deploying alkali hydroxides/amine solutions or amine‐modified materials still suffer from unsolved high energy consumption and stability issues. In this work, composite sorbents are crafted by hybridizing a robust metal‐organic framework (Ni‐MOF) with superbase‐derived ionic liquid (SIL), possessing well maintained crystallinity and chemical structures. The low‐pressure (0.4 mbar) volumetric CO 2 capture assessment and a fixed‐bed breakthrough examination with 400 ppm CO 2 gas flow reveal high‐performance DAC of CO 2 (CO 2 uptake capacity of up to 0.58 mmol g −1 at 298 K) and exceptional cycling stability. Operando spectroscopy analysis reveals the rapid (400 ppm) CO 2 capture kinetics and energy‐efficient/fast CO 2 releasing behaviors. The theoretical calculation and small‐angle X‐ray scattering demonstrate that the confinement effect of the MOF cavity enhances the interaction strength of reactive sites in SIL with CO 2 , indicating great efficacy of the hybridization. The achievements in this study showcase the exceptional capabilities of SIL‐derived sorbents in carbon capture from ambient air in terms of rapid carbon capture kinetics, facile CO 2 releasing, and good cycling performance.