| Metal-organic framework（MOFs）materials are crystalline materials of an infinite lattice structure composed of metal ions or metal clusters and organic ligands which are alternately connected by coordination bonds.As novel inorganic-organic hybrid porous materials,the structure of MOFs can be adjusted and designed,thus MOFs have rich topological structure,adjustable pore size and high specific surface area.Such materials have broad potential applications in gas adsorption/separation,catalysis,molecular magnetism,luminescent and recognition and so on.In the synthesis of MOFs,the choice and design of metal ions,especially organic ligands,are essential for constructing MOFs with specific functions.The rational synthesis of MOF materials with specific properties can be achieved by design and synthesis of the organic ligands,as well as the selection of metal ions.In this paper,we design and synthesize a new ligand with aggregation-induced emission effect（AIE）.By using this ligand,we have successfully synthesized two types of MOFs containing transition and lanthanide metals in the solvothermal synthetic system by modulating reaction conditions.The structures and properties of these MOFs are studied.The main results in the thesis are summarized as follows:1.A new tetraphenylpyrazine-based tetracarboxylic ligand 2,3,5,6-tetrakis（4-carboxyphenyl）pyrazine（H4TCPP）has been designed and synthesized based on the following reasons.First,H4 TCPP possesses a rigid skeleton similar to 4,4′,4′′,4′′′-benzene-1,2,4,5-tetrayltetrabenzoic acid（H4BTTB）,which can be easily synthesized from methyl 4-formylbenzoate.Second,there are two N atoms within the pyrazine core,which is propitious to enhance the adsorption ability for CO2 and the sensing selectivity for analytes.Finally and most importantly,the AIE effect of H4 TCPP will endow MOFs with interesting luminescent property.2.A three-dimensional transition MOF materials（Zn-TCPP）was successfully synthesized by using a new rigid highly symmetric tetracarboxylic acid H4 TCPP and a metal source of Zn（NO3）2·6H2O under solvothermal conditions.Single crystal X-ray structure analysis shows that Zn-TCPP crystallizes in an orthorhombic space group of Imma.Its framework is composed of paddlewheel dinuclear Zn2（COO）4 clusters and organic TCPP4-ligands which are connected to form 3D channel structure.TOPOS analysis shows that Zn-TCPP has a four connected lvt topology with the point symbol of {42.84}.Zn-TCPP displays bright blue luminescence benefiting from the matrix coordination-induced emission effect of TCPP4-ligand.Due to the presence of free N groups of pyrazine in the H4 TCPP,Zn-TCPP could be used to detect picric acid and Fe3+ ions.Moreover,the activated Zn-TCPP possesses highly porous framework which has a large surface area with a value of 984 m2 g-1.It has a high adsorption capacity of CO2,reaching 135 cm3g-1 in 273 K and 732 mmHg.3.Two two-dimensional lanthanide MOFs（Eu-TCPP and Tb-TCPP）were successfully synthesized from organic ligand H4 TCPP and metal source of EuCl3 and TbCl3 under solvothermal conditions.The single crystal X-ray structure analysis shows that their frameworks are composed of dinuclear RE2（COO）6 and organic TCPP4-ligands resulting in a 2D layer structure,which crystallize in triclinic space group of P-1.TOPOS analysis shows that Eu-TCPP and Tb-TCPP have a 3,6-connected kgd topology with the point symbol {43}2{46.66.83}.In addition,Eu-TCPP has good flurescence properties,the microcrystalline phase of Eu-TCPP can also be used to detect PA and Fe3+ ions due to the presence of N atoms in H4 TCPP. |
