Synthesis And Properties Of Metal-Organic Frameworks Based On Bis-triazolate And Bifunctional Tetrazolate Ligands

With rapid development and playing a key role in energy, materials and life sciences, Metal-Organic Frameworks (MOFs) are one such important type of solid-state materials with great prospects of practical applications. According to the principle of molecular design, thirteen novel MOFs based on the triazolate and tetrazolate ligands have been synthesized and determined by X-ray single crystal diffraction analysis. These complexes have been characterized by elemental analysis, IR, variable temperature magnetic susceptibility measurements, fluorescence and N₂, H₂ absorption measurements. The main contributions in this work are blow:1. A novel 2D Mn(II) MOF with 4,4'-bis-1,2,4-triazole (btr) has been obtained. Strong antiferromagnetic interactions between Mn(II) ions are observed.2. To obtain more information on supramolecular architecture construction and btr-metal coordinated structures, eight complexes of btr and M(II) (M = Cu and Cd) have been successfully synthesized, one of which is the first example of theμ₃- andμ₂-btr simultaneity in a single system in triazole-metal complexes. The variety of dimensionalities based on the tuning of different anions and metal centers were detailed discussed. Variable-temperature magnetic susceptibility studies on the Cu(II) compounds reveal the overall antiferromagnetic behaviors.3. A novel 3D porous MOF built with 2,6-di-(4-triazolyl)pyridine (dtp) and Cd(II) has been synthesized and characterized as a promising luminescent material that can give tunable emissions between UV and visible wavelengths by controlling the number of the guest molecules.4. Using 4-(2H-tetrazol-5-yl)benzoic acid (4-H₂TzB), three of Mn(II) and Mg(II) novel 3D porous MOFs have been synthesized. The trial N₂, H₂ absorption isotherms have been determined. This part of research was supervised by Prof. Jeffrey. R. Long in University of California, Berkeley, USA, as a visiting student researcher.