Periodic Precipitation of Zeolitic Imidazolate Frameworks in a Gelled Medium

Formation of spatially periodic patterns is a ubiquitous process in nature and man-made systems. Periodic precipitation the oldest type pattern formation, which formed colloid particles are self-assembled into sequence separated zones solid hydrogels. Chemical systems exhibiting mostly comprise oppositely charged inorganic ions. Here, we present new sub-group this phenomenon driven by diffusion reaction several transition metal cations (Zn2+, Co2+, Cd2+, Cu2+, Fe2+, Mn2+, Ni2+) with an organic linker (2-methylimidazole) producing zeolitic imidazolate frameworks. In some cases, crystals reached size ∼50 μm showing that gel matrix can provide optimal conditions for nucleation crystal growth. We investigated effect concentration solvent composition on morphology pattern. To support experimental observations, developed reaction–diffusion model, qualitatively describes formation.