A MOF‐based Ultra‐Strong Acetylene Nano‐trap for Highly Efficient C2H2/CO2 Separation

Abstract Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C 2 H 2 /CO 2 . Herein, we propose a new type of ultra‐strong C 2 H 2 nano‐trap based on multiple binding interactions to efficiently capture C 2 H 2 molecules and separate C 2 H 2 /CO 2 mixture. The ultra‐strong acetylene nano‐trap shows a benchmark Q st of 79.1 kJ mol −1 for C 2 H 2 , a record high pure C 2 H 2 uptake of 2.54 mmol g −1 at 1×10 −2 bar, and the highest C 2 H 2 /CO 2 selectivity (53.6), making it as a new benchmark material for the capture of C 2 H 2 and the separation of C 2 H 2 /CO 2 . The locations of C 2 H 2 molecules within the MOF‐based nanotrap have been visualized by the in situ single‐crystal X‐ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C 2 H 2 .