Crystal seeds induced interfacial growth of zirconium metal-organic framework membranes towards efficient hydrogen purification

Metal-organic frameworks (MOF) membranes with tunable pore size and versatile functions are promising for gas separation. Nevertheless, it still remains a great challenge to prepare defect-free high-valence MOF membrane with high stability. Herein, we report fabrication of high-valence Zr-MOF membranes by a crystal seeds induced interfacial growth approach. A MOF-802 seeding layer was deposited on the substrate surface, providing nucleation sites to induce intergrowth of MOF-802 into crystalline membrane when metal source and ligand diffuse in opposite directions to coordination react on the surface of porous substrate. The resulting continuous MOF-802 membrane displays excellent H2/CO2 separation performance with H2 permeance of-3540 GPU and selectivity of-23.1, transcending the upper-bound of state-of-the-arts. The MOF-802 membrane also shows high separation efficiency in the presence of water vapor owing to the excellent water stability of the framework. This work provides a facile approach and fundamental transport property for developing high-valence MOF molecular sieving membranes.