CO 2 ‐triggered transformation of switchable porous deep eutectic solvents to porous ionic liquids for CO 2 separation

Here, we develop a methodology to prepare a class of CO 2 ‐triggered switchable porous deep eutectic solvents (PDESs) by anchoring DBU/alcohol pairs onto the surface of UiO‐66‐NH 2 nanoparticles. Notably, CO 2 can trigger the transformation of PDESs into porous ionic liquids (PILs), and the reverse process can be achieved by bubbling transformation N 2 at 50°C. The as‐prepared PDESs achieved excellent separation of both CO 2 /C 2 H 2 and CO 2 /CH 4 . Combined density functional theory, molecular dynamics, and grand canonical Monte Carlo simulations confirm that the outstanding performance is mainly attributed to the DBU/alcohol pair, which serves as a functional layer that selectively recognizes CO 2 . Considering the diversity of porous hosts, the applicability of this methodology was confirmed by replacing the porous host. To our knowledge, this is the first study to disclose the transition between DESs and ILs using CO 2 in porous liquids.