Preorganization and Cooperation for Highly Efficient and Reversible Capture of Low‐Concentration CO 2 by Ionic Liquids

A novel strategy based on the concept of preorganization and cooperation has been designed for a superior capacity to capture low‐concentration CO 2 by imide‐based ionic liquids. By using this strategy, for the first time, an extremely high gravimetric CO 2 capacity of up to 22 wt % (1.65 mol mol −1 ) and excellent reversibility (16 cycles) have been achieved from 10 vol. % of CO 2 in N 2 when using an ionic liquid having a preorganized anion. Through a combination of quantum‐chemical calculations and spectroscopic investigations, it is suggested that cooperative interactions between CO 2 and multiple active sites in the preorganized anion are the driving force for the superior CO 2 capacity and excellent reversibility.