writer：Lingzhi Yang, Liting Yan*, Weijing Niu, Yan Feng, Qiuju Fu, Shuo Zhang, Yinhang Zhang, Liangjun Li,
keywords：C2 Hydrocarbons；C2H6/C2H4 Separation；Fluorinated Metal-OrganicFramework；Hydrogen Bond；Perfluorinated Channels
source：期刊
specific source：ANGEWANDTE CHEMIE-INTERNATIONAL EDITION，2022，61, 25，e202204046
Issue time：2022年
Metal-organic frameworks have been widely studied in the separation of C-2 hydrocarbons, which usually preferentially bind unsaturated hydrocarbons with the order of acetylene (C2H2)>ethylene (C2H4)>ethane (C2H6). Herein, we report an ultramicroporous fluorinated metal-organic framework Zn-FBA (H(2)FBA=4,4 ''-(hexafluoroisopropylidene)bis(benzoic acid)), shows a reversed adsorption order characteristic for C-2 hydrocarbons, that the uptake for C-2 hydrocarbons of the framework and the binding affinity between the guest molecule and the framework follows the order C2H6>C2H4>C2H2. Density-functional theory calculations confirm that the completely reversed adsorption order behavior is attributed to the close van der Waals interactions and multiple cooperative C-H...F hydrogen bonds between the framework and C2H6. Moreover, Zn-FBA exhibits a high selectivity of about 2.9 for C2H6 over C2H4 at 298 K and 1 bar. The experimental breakthrough studies show that the high-purity C2H4 can be obtained from C2H6 and C2H4 mixtures in one step.