Design, Syntheses and Characterization of Multifunctional Organic-Inorganic Hybrid Materials

Abstract

Multifunctional Metal-organic frameworks (MOFs) have been the theme of cutting edge research in the modern era. Because of diversified structures, structural tunability and targeted host-guest interactions in these porous architectures, MOFs have shown promising potential in terms of applicability in almost all spheres of material science. From the designing aspect, one of the key strategies is choice of ligands used in MOF syntheses. Neutral nitrogen donor ligands lead to formation of cationic frameworks resulting in the occupancy by extra framework anions for balancing overall charge of the frameworks. Such framework cations can often be exchanged with exogenous anions resulting in not only structural changes, but also visual colorimetric changes depending on the judicious choice of the metal centre such as Cu (II) ions. On the other hand Dicarboxylate based ligands are the most widely used ligands used in fabrication of such porous frameworks. Anionic carboxylate linkers not only give rise to robust and rigid MOFs but also in some cases flexible frameworks may result giving rise to multi-variant functionalities. From the application perspective if a MOF material can be down sized in Nano metric scale, then they can be efficiently used as mixed matrix membranes (MMMs) in conjunction with organic polymers for addressing one of the key global problems i.e. separation of CO2 from other gases. Bearing this in mind, my thesis work pivots around design, syntheses and characterization of two metal-organic hybrid materials for a) naked eye colorimetric anion sensing b) development of MOF based MMMs for CO2 separation.