H2O-Functionalized Zeolitic Zn(2-methylimidazole)2 Framework (ZIF-8) for H2 Storage

It is generally recognized that H2O adsorption on a porous material would inhibit H-2 adsorption. However, this paper reports that stable H2O-fiinctionalized zeolitic Zn(2-methylimidazole)2 framework (ZIF-8), which was obtained by the simple water treatment of ZIF-8 at ambient temperature, can increase its H-2 adsorption heat from 5.2 to 10.1 kJ/mol. As a result, the reversible H-2 capacity at ambient temperature increased by 77%. This indicates that H2O functionalization provides a novel approach to enhance ambient-temperature hydrogen storage in ZIF-8 and other metal-organic frameworks.