Synthesis of ZIF-68 Crystals and Membranes On ZnO Supports Using Reactive Seeding Method

摘要

In recent years, hybrid materials known as metal-organic frameworks (MOFs) have begun garnering a sizeable amount of attention. Similar to zeolite membranes, large pore MOF-5 membranes exhibit good adsorption-controlled perm-selectivity for carbon dioxide over less adsorbing gases such as nitrogen. However, MOF-5 is amenable to degradation in humid atmosphere. Zeolitic imidazolate frameworks (ZIFs), a specific MOF wherein the topologies mimic those of zeolites, except with the advantages of the hybrid structure and organic ligands, are structurally more stable than MOFs. This paper reports the synthesis of crystals and membranes of ZIF-68, a highly crystalline, larger pore (pore diameter of 0.75 nm) ZIF analog to MOF-5. The work is the first effort to synthesize ZIF-68 membranes.