Reactive Extrusion Printing for Simultaneous Crystallization-Deposition of Metal–Organic Framework Films

Reactive extrusion printing (REP) is demonstrated as an approach to simultaneously crystallize and deposit films of the metal–organic framework (MOF) Cu3btc2 (btc=1,3,5-benzenetricarboxylate), also known as HKUST-1. The technique co-delivers inks of the copper(II) acetate and H3btc starting materials directly on-surface and on-location for rapid nucleation into films at room temperature. The films were analyzed using PXRD, profilometry, SEM and thermal analysis techniques and confirmed high-quality Cu3btc2 films are produced in low-dispersity interconnected nanoparticulate form. The porosity was examined using gas adsorption which showed REP gives Cu3btc2 films with open interconnected pore structures, demonstrating the method bestows features that traditional synthesis does not. REP is a technique that opens the field to time-efficient large-scale fabrication of MOF interfaces and should find use in a wide variety of coating application settings.