Tuning Multiple Counter-Anions in Porous Coordination Polymers with lcy Topology for Acetylene/Ethylene Separation.

The efficient separation of acetylene (C 2 H 2 ) and ethylene (C 2 H 4 ) is an important and complex process in the industry. Herein, we report a new family of lcy -topologic coordination frameworks (termed NTU-90 to NTU-92 ) with Cu 3 MF 6 (M = Si, Ti, and Zr) nodes. These charged frameworks are compensated by different counterbalanced ions (MF 6 2- , BF 4 - , and Cl - ), yielding changes in the size of the window apertures. Among these frameworks, NTU-92-a (activated NTU-92 ) shows good adsorption selectivity of C 2 H 2 /C 2 H 4 and also significant ability in recovering both highly pure C 2 H 4 (99.95%) and C 2 H 2 (99.98%). Our work not only presents a potential alternative for energy-saving purification of C2 hydrocarbons but also provides a new approach for tuning the function of charged porous materials.