Advances of Metal-Organic Framework Stationary Phases for Gas Chromatographic Separations

Metal-organic frameworks (MOFs) are porous materials composed of metal ions or metal clusters and organic ligands by coordination, which have the advantages of large specific surface area, good thermal stability and adjustable pore size, and have a promising application in gas chromatographic separation. In recent years, MOFs materials have been used as stationary phases for gas chromatography mainly including ZIF, MIL, UiO-66, HKUST-1, IRMOFs, etc. Based on the molecular sieve effect, van der Waals forces, hydrogen bonding and 'r-'r interactions, the pore size, pore microenvironment, unsaturated metal site and special functional group of the MOFs stationary phase materials can be specifically designed and regulated. MOFs materials as stationary phases have unique separation performance for n-alkanes and their isomers, aromatic compounds and their isomers, alcohols/ ketones/aldehydes and their isomers, and chiral compounds. The combination of organic polymers and novel nanomaterials with MOFs materials can improve the separation performance and stability of MOFs. Therefore, MOFs materials are expected to be the promising stationary phase that can be applied to gas separation in complex environments. In this article, the research advances of various stationary phases based on MOFs for gas chromatography in recent years were reviewed. The separation performance and separation mechanism of MOFs stationary phases for mixed gas samples were discussed, and the development trends in the future were prospected.