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Metal–organic frameworks (MOFs) built up from Zr6-based nodes and multi-topic carboxylate linkers have attracted attention due to their favourable thermal and chemical stability. However, the hydrolytic stability of some of these Zr6-based MOFs has recently been questioned. Herein we demonstrate that two Zr6-based frameworks, namely UiO-67 and NU-1000, are stable towards linker hydrolysis in H2O, but collapse during activation from H2O. Importantly, this framework collapse can be overcome by utilizing solvent-exchange to solvents exhibiting lower capillary forces such as acetone.

Crystalline metal–organic frameworks (MOFs) have emerged as a highly desirable class of solid-state materials. Some of their most attractive features include exceptionally high porosities as well as surface areas. A key aspect to the realization of high porosity is the removal of guest molecules from the framework while still maintaining its structural integrity (i.e., “activation”). This contribution highlights the strategies utilized to date for activating MOFs, including: (i) conventional heating and vacuum; (ii) solvent-exchange; (iii) supercritical CO2 (scCO2) exchange; (iv) freeze-drying; and (v) chemical treatment.