New strategies based on microfluidics for the synthesis of metal–organic frameworks and their membranes

Metal-organic frameworks (MOFs) are highly porous crystalline materials formed by the coordination of organic ligands with metal clusters. Despite the significant progress in their development over the last few years and their applications in various classic and emerging fields, the control of their shape and size remains a challenge, in particular the search for more efficient and environmentally friendly syntheses. In this context, the microfluidics approach allows not only the continuous production of MOFs but also an accurate reaction parameter control in their synthesis, representing a step towards intensification, versatility and scalability in the use of MOFs. Microfluidics also offers the possibility of synthesizing effective and defect free MOF-based hollow fiber membranes saving reactants as compared to conventional methods. This review is devoted to highlighting the multitude of synergies appearing when dealing with MOFs and microfluidics, not only in the bare synthesis of MOFs and their hierarchical structures but also when fabricating hollow fiber membranes with important applications in the separation field.