Microporous Copper Isophthalate Framework of mot Topology for C2H2/CO2 Separation

Separating acetylene (C2H2) from carbon dioxide (CO2) is highly challenging under mild conditions owing to their extreme similarity in molecular properties. Herein, a mot-type microporous metal–organic framework [Cu(BDC-Br)(H2O)0.5(DMF)2.5] (H2BDC-Br = 4-bromoisophthalic acid, DMF = N,N′-dimethylformamide) featuring a dicopper paddlewheel, has been evaluated for C2H2/CO2 separation. Gas sorption measurements have revealed this MOF exhibits considerable C2H2 uptake capacity with a C2H2/CO2 selectivity of 3.9 at room temperature and 1 atm. The separation performance was further illustrated by breakthrough experiments upon a 50/50 C2H2/CO2 mixture, suggesting the potential of this material for challenging separation of C2H2/CO2.