Microscopic Mechanical Force-Driven Amorphization of Metal-Organic Frameworks

While metal-organic frameworks (MOFs) are renowned for their highly ordered crystalline structures, the amorphization of MOFs reveals new functional properties and creates opportunities for material innovation. In this study, we present a novel microscopic mechanical force-driven amorphization that occurs within a polycrystalline metal-azolate framework (MAF-5) membrane. We show that vapor flow during pervaporation across the membrane generates localized mechanical stresses that disrupt the ordered crystalline lattice. This mechanical amorphization is significantly influenced by the physical properties of the permeating organic solvents, underscoring the importance of solvent-framework interactions. Our findings unveil a previously unknown mechanical mechanism that drives MOF amorphization and provide essential insights into their mechanical tunability, facilitating the design of amorphous MOF membranes with customized properties for advanced applications.