Studies On The Construction And Properties Of Cluster-based Metal-Organic Frameworks

Metal-Organic Frameworks （MOFs） with adjustable functionalities combining withaccessible structure modification have been increasingly accelerated and sustainedexpansion which point directly toward their potential applications in gas storage andcapture, catalysis, nanoscale magnetism, drug delivery, and sensor devices. As oneimportant research area of the MOFs, the cluster-based MOFs are most attractive dueto the polynuclear clusters as secondary building units （SBUs） can release more suf-ficient capacity and also can improve the thermal stability of the whole frameworks.In this thesis, a series of cluster-based compounds by incorporating different polynu-clear clusters as SBUs have been synthesized on the basis of solvothermal or hydro-thermal technique and structurally characterized by single crystal X-ray diffractions,IR spectrum, elemental analyses, TG and XRD. The topological analyses, fluorescentspectrum, gas adsorption properties, and magnetic properties of these compoundshave also been investigated. The dissertation includes five chapters as below:In chapter1, a brief introduction of the research background and the current pro-gresses on MOFs, especially the synthesis and construction of MOFs based on clus-ter-based SBUs, are concisely presented. Moreover, the fundamental and the pro-gresses of this work have also been outlined.In chapter2, eight new cluster-based MOFs have been solvothermally synthesizedand structurally characterized by the reaction of1,3,5-benzenetricarboxylic acid（H3BTC） with Fe^Ⅲ、Zn^â…¡and Cd^â…¡ions. These compounds are mainly constructed frommononuclear-, peddle-wheel dinuclear-, trinuclear-clusters and rod-shaped chain asSBUs, respectively. Furthermore, the magnetic properties and gas adsorption proper-ties of some compounds have also been discussed.In chapter3, we introduced benzotriazolate （HBTA） and its derivative to “cap-ture” more metal ions using the tri-N-donor property of the triazolate group whichcan provide more coordination sites for metal centers to form polynuclear clusters asSBUs. Based on this strategy, eleven cluster-based MOFs have been isolated based on dinuclear-, trinuclear-, heterometallic tetranuclear-, pentanuclear-and nonanu-clear-clusters and rod-shaped chain as SBUs, respectively. Moreover, the luminescentproperties, gas adsorption properties, and magnetic properties of these compoundshave also been investigated.In chapter4, eight new cluster-or ring-based compounds have been synthesizedby the in situ [2+3] cycloaddition reactions of different dinitriles, NaN₃in the pre-sent of meal salts and various neutral N-donor ligands. The compounds are basicallyestablished on mononuclear-, dinuclear-and heptanuclear-clusters, four memberedmetals ring, six membered metals ring and rod-shaped chain as SBUs, respectively. Inaddition, the magnetic and luminescent properties of some compounds have also beeninvestigated.In chapter5, a conclusion on this work and a perspective have been presented.