Identifying pathways to metal-organic framework collapse during solvent activation with molecular simulations (original) (raw)
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Metal-organic frameworks (MOFs) are an emerging, class of porous materials. MOFs are highly ordered, crystalline coordination polymers of persistent porosity with specific surface areas exceeding that of traditional adsorbents, such as zeolites and active carbons. Whereas initial research on MOFs was mainly driven by the interest to use them as gasstorage (e.g. CH 4 , H 2 , CO 2 ) materials, various other applications were proposed and demonstrated, including separation, sensing, catalysis, drug release, and the embedding of (metal and metal oxide) nanoparticles. Presently, the search for new types of MOFs is largely by trial-and-error, because very little is known about the details of the MOF crystal growth and nucleation process. In a 2006 review article on MOFs by Cheetham et al. it was noted that there was still no in situ characterization of an assembly process for MOFs on the molecular level. In this assembly process two subunits have to be combined, organic ligands and metal precursors. Whereas the organic ligands are
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Metal-organic frameworks (MOFs) are highly tunable, extended-network, crystalline, nanoporous materials with applications in gas storage, separations, and sensing. We review how molecular models and simulations of gas adsorption in MOFs have lucidly impacted the discovery of performant MOFs for methane, hydrogen, and oxygen storage, xenon, carbon dioxide, and chemical warfare agent capture, and xylene enrichment. Particularly, we highlight how large, open databases of MOF crystal structures, post-processed for molecular simulations, are a platform for computational materials discovery. We pontificate how to orient research efforts to routinize the computational discovery of MOFs for adsorption-based engineering applications.