Bicontinuous Zeolitic Imidazolate Framework ZIF-8@GO Membrane with Enhanced Hydrogen Selectivity

Through layer-by-layer (LBL) deposition of a graphene oxide (GO) suspension on a semicontinuous ZIF-8 layer, we have developed a novel bicontinuous ZIF-8@GO membrane. Since only the gaps between the ZIF-8 crystals are sealed by the GO layer due to capillary forces and covalent bonds, the gas molecules can only permeate through the ZIF-8 micropore system (0.34 nm). Therefore, the ZIF-8@GO membranes show high hydrogen selectivity. At 250 OE C and 1 bar, the mixture separation factors of H-2/CO2, H-2/N-2, H-2/CH4, and H-2/C3H8 are 14.9, 90.5, 139.1, and 3816.6, with H-2 permeances of about 1.3 x 10(-7) mol.m(-2).s(-1).Pa-1, which is promising for hydrogen separation and purification by molecular sieving