Investigating size-dependent structural flexibility in ZIF-7: Effect of the crystal size in alcohol separation.

Understanding the atomic-scale flexibility of Zeolitic Imidazolate Frameworks (ZIFs) is crucial for their use in adsorption, separations, and sensing technologies. Among them, ZIF-7 exhibits guest-induced flexibility, but the relationship between its structural dynamics, guest loading, and particle size remains unclear. This study will explore how alcohol-induced phase transitions in ZIF-7 are modulated by particle size, bridging a key gap in designing flexible MOFs for separations. Preliminary in-situ PXRD with 1-propanol reveals reversible phase transitions linked to framework flexibility, guest occupancy, and crystallite size. To elucidate these mechanisms, high-resolution in-situ synchrotron PXRD studies of ZIF-7 across the nano- to microscale under controlled alcohol vapour environments will provide crucial insights into the controlled phase transitions in ZIF-7, linking nanoconfinement effects to macroscopic performance in industrial applications.