Recovery of MOF-5 from Extreme High-Pressure Conditions Facilitated by a Modern Pressure Transmitting Medium

Mechanisms underlying the mechanically induced amorphization of metal–organic frameworks (MOFs) are of current interest, and both high-pressure experimentation and molecular dynamics simulations have been used to reveal the fundamentals of load bearing, deformation, and pressure-induced amorphization (PIA) in these highly porous materials. Unfortunately, MOFs are typically highly susceptible to amorphization, which limits the conditions under which they can be processed and used. However, their flexible structures can be stabilized at high pressures by incorporating guest species into the framework matrix. In this study, a large-molecule pressure transmitting medium (DAPHNE 7575) is used as a structure-fortifying guest species to stabilize the prototypical MOF-5 at high pressures (>9 GPa) and enable the recovery of crystalline material upon decompression. Structural changes associated with the penetration of the pressure transmitting medium on compression are examined using a combination of high-pressure synchrotron powder diffraction and molecular dynamics simulations. This work enhances the understanding of PIA in MOFs while showcasing a potential route for the stabilization of MOFs at surprisingly high pressures.