(349j) High-Throughput Synthesis and Screening of Metal-Organic Frameworks (MOFs) - an Effort Towards Discovery of Next-Generation Materials

High-throughput screening has been widely deployed in the field of inorganic and organic crystallization. This technique has proved useful to study the effects of the synthesis conditions and precursor concentration on the final size, morphology and crystallinity of the obtained product. In the field of Metal- and Covalent-Organic Frameworks (MOFs and COFs), this approach has been introduced for screening the morphology and crystallinity of a few systems. In this work, a high-throughput screening method for synthesizing high-entropy MOFs and other MOF systems has been developed. Effects of precursor conditions (metal & linker concentrations, modulator concentrations, etc.) and temperature conditions on the final quality attributes of the MOF have been studied. The obtained MOF powder has been characterized for composition using infrared and Raman spectroscopy and crystallinity powder X-ray diffraction (P-XRD) in high-throughput mode. Selective samples have been characterized for morphology using electron microscopy. Along with powdered MOF synthesis, efforts have been made to deposit the MOFs on appropriate substrates in the high-throughput super-structure. These depositions are further deployed to screen their conductivity and activity toward CO₂-RR with the help of a robotic arm mounted with a counter and reference electrode. The obtained input-output data is coupled with machine learning techniques to train the model with the role of conditions on the final attributes and predict the MOF attributes for a test dataset.