Fabrication of Crystalline Microporous Membrane from 2D MOF Nanosheets for Gas Separation.

Metal-organic frameworks (MOFs)-based membranes have shown great potentials as applications in gas separation. In this work, a uniform membrane based on 2D MOF Ni (HITP) (HITP=2,3,6,7,10,11-hexaaminotriphenylene) was fabricated on ordered macroporous AAO via the filtration method. To fabricate the membrane, we obtained the Ni (HITP) nanosheets as building blocks via a soft-physical exfoliation method successfully that were confirmed by AFM and TEM. We also studied the H , CO and N adsorption isotherms of Ni (HITP) powder at room temperature, which shows Ni (HITP) has high heats of adsorption for CO and high selectivity of CO over N . Gas permeation tests indicate that the Ni (HITP) membrane shows high permeance and selectivity of CO over N , as well as good selectivity of H over N . The ideal separation factors of CO /N and H /N from sing-gas permeances are 13.6 and 7.8 respectively, with CO permeance of 3.15×10  mol⋅m ⋅s ⋅Pa . The membrane also showed good stability, durability and reproducibility, which are of potential interest for practical applications in the CO separations.