A versatile microfluidic strategy using air-liquid segmented flow for continuous and efficient synthesis of metal-organic frameworks

Microfluidic synthesis is one of the most state-of-the-art methods for preparing metal-organic frameworks (MOFs) attributed to its high mass/heat transfer efficiency and controllable reaction process. However, the post -processing of the products in most of the currently reported liquid-liquid microfluidic synthesis methods is complicated and can burden the environment due to the using of oil phase. Herein, we report a simple, efficient and versatile method for the preparation of MOFs through an air-liquid segmented flow reaction. Six classical MOFs (HKUST-1, Co-MOF-74, Cu-BDC, MOF-801, UiO-66 and MOF-808) with homogeneous morphologies and different topologies are successfully synthesized by the air-liquid segmented flow method. The prepared A-MOFs exhibited high crystallinity, high space-time yield (STY), homogeneous morphology, smaller particle size, higher surface area compared to the samples synthesized by the solvothermal method, which will benefit the practical applications of MOFs in many fields, such as gas adsorption, catalysis and so on.

Automated summary

Microfluidic synthesis is an advanced method for preparing metal-organic frameworks (MOFs) due to its efficiency in mass/heat transfer and controllable reaction process. However, the post-processing in most liquid-liquid methods is complicated and environmentally burdensome. This study introduces a simple and efficient air-liquid segmented flow method for synthesizing MOFs, resulting in six different MOFs with high crystallinity, yield, and homogeneous morphology compared to traditional solvothermal methods. These prepared MOFs can be applied in various fields such as gas adsorption and catalysis.