| Metal-Organic Frameworks(MOFs)have important research significance in many fields,such as gas storage and separation,fluorescent sensors and catalysis,due to their excellent characteristics as large specific surface area,diverse pore structures,easy modification of pore surfaces and more unsaturated metal sites.With the increasing demand for material performance,single MOFs are no longer sufficient to meet the needs of the times,and the research focus has shifted from novel structures to the preparation of functionalized MOFs.It's significant that pre-design of organic linker with active sites to optimize the affinities between guest molecules and host frameworks,which can improve the adsorption amount of distinctive adsorbate;meanwhile,the introduction of specific fluorescence-responsive moieties can also afford versatile chemo-sensors with high selectivity and sensitivity.Among the many MOFs materials,amino-modified MOFs have attracted a lot of attention.The amino groups in MOFs materials possess the ability to accept protons and provide electron pairs,and often show good adsorption properties for small molecules.Meanwhile,amino-modified aromatic organic molecules have strong absorption in the UV region,which exhibit good luminescence properties.The aim of this paper is to design and synthesize porous metal-organic frameworks compounds with amino modification.The structures of these compounds were characterized in detail using some characterization tools,such as X-ray single crystal diffraction,PXRD,FT-IR,etc,and the applications of these materials in adsorption,fluorescence sensing were investigated.The specific work is as follows:1.The novel structure of compound 1,[Ni(3-NH2-pba)2]·2H2O·2DMF was successfully constructed by self-assembly of 3-NH2-Hpba was used as the organic linker and metal Ni as the building block.Single-crystal X-ray diffraction analysis revealed that compound 1 is a quadruple interspersed dia topological network in[2+2]mode.The results showed that the adsorption capacity of compound 1 for C2H2,C2H4,CO2,CH4 and N2 were 134.8 cm~3/g,101.5 cm~3/g,125.3 cm~3/g,29.9 cm~3/g,8.0 cm~3/g at 1 atm,273 K,respectively.At 298 K,the adsorption capacities for C2H2,C2H4,CO2,CH4,and N2 were 99.3 cm~3/g,78 cm~3/g,86.6 cm~3/g,20.3 cm~3/g,and 5.4 cm~3/g,respectively.Besides,the initial CO2/CH4(50:50),C2H4/CH4(50:50)and C2H2/CH4(50:50)selectivity values are 1.93,15.39 and 22.59 at 273 K,and 2.16,9.60 and 9.41at 298 K,respectively.Meanwhile,this compound 1 exhibits a high iodine capture of558 mg/g in hexane.2.A novel structure of compound 2,[Cd(3-NH2-pba)2]4·8DMF was synthesized by self-assembly with 3-NH2-Hpba as the organic linker and metal Cd as the building block;Single-crystal X-ray diffraction analysis revealed that compound 2 is a five-fold interspersed dia topological network in the[3+2]mode.The compound has a special fluorescence response and can be used as a“Turn-Off”type fluorescent probe to detect trace water in ethanol.It is worth noting that the detection limit is 0.09%,which was lower than the international requirement for the combustion value of hydrated ethanol.Meanwhile,it can also be developed as an unusual“Turn-On”sensor for the probe of Ag+in aqueous solution with the detection limit to 0.44 m M,which was lower than the maximum concentration of Ag+in drinking water according to the standard of the U.S.Environmental Protection Agency.3.A structurally novel compound 3,[Zn2(3-NH2-pda)2(pbdc)]·DMF·2H2O was synthesized by self-assembly using 3-NH2-Hpba,terephthalic acid as the organic linker and metal Zn as the building block;Single-crystal X-ray diffraction analysis reveals that this compound exhibited a two-fold interpenetration of pcu net and coordination-free amino groups distribute into the channels.For its excellent thermal and water stability,this compound can be developed as a“Turn-On”sensor for the probe of Ag+in aqueous solution with the detection limit to 0.76?M.Meanwhile,this compound 3 exhibits a high iodine capture of 228 mg/g in hexane. |
PDF Full Text Request