| Metal-organic frameworks(MOFs)class function coordination polymer is the hotspot in the field of chemistry and forefront,many scientists at home and abroad long-term research and continuous,related research breakthrough unceasingly,has been in the energy storage,selective separation,heterogeneous catalysis,molecular recognition,optical/electric/magnetic function,shows the unique performance,many aspects,such as biomedical and steadily push forward to the future industrial application.In synthetic chemistry,utilization of simple structure,low cost of organic ligands useful structure and function,to promote MOFs future real application is of great significance to practice;In crystal engineering,system research the preset geometric configuration of organic ligand coordination assembly rule,is the only way to explore MOFs function oriented controllable preparation.In this thesis,the simplest and most accessible 1,3,5-benzenetricarboxylic acid and its-NH2,-Br substitutions were selected as the main ligands,and the 3d post-transition metal ions with abundant reserves and lower cost than rare earth ions were selected for crystal engineering exploration.The ligand expansion of 1,3,5-Tris[4-carboxyphenyl]benzene carboxylic acid was carried out to study and compare the crystal engineering laws of triangular benzene carboxylic acid ligands of different sizes.Furthermore,on the basis of studying the coordination assembly law of linear benzene carboxylic acid ligands,the porous network structure of triangular and linear ligands is also explored.23 new MOFs were successfully prepared,their structures were analyzed and their properties of fluorescence,adsorption and post-synthesis metal ion replacement were studied.The thesis includes the work of the following four parts:1.Mainly described lower cost triangular ligand 1,3,5-benzenetricarboxylic acid(H3btc)with Zn(?)?Cd(?)?Mn(?)and Pb(?)ions features and the regularity of construction of coordination compounds.Eight cases of MOFs was synthesized:[Me2NH2]6[Zn16(btc),2(gac)(DMA)3(H2O)3](1),[Me2NH2][Cd(btc)]·0.5DMA·2H2 O(2),[Me2NH2]2[Cd;(btc)2(lac)3(H2O)3]·4DMF(3),[Me2NH2][Mn?(btc)]·DMA(4),[Me4N]3[Mn?3(btc)2(Hbtc)(5),[Me2NH2]2[Zn5(btc)4(DMA)2]·5.5DMA(6),[Pb3(btc)2(EtOH)]·4EtOH(7)and[Cu4(btc)(CN)](8).The compound 1 crystallographic asymmetric cell contains 16 Zn2+ ions,12 btc3-ligands.Because the multiple chemical environments of metal ions and ligands cause their electron energy levels to overlap,Compound 1 exhibited continuous wideband fluorescence under ultraviolet excitation,The emission spectrum covers the whole visible spectral region and is close to the pure white light CIE(0.33,0.33).It was a new type of recent light white light material and has been successfully used in the preparation of WLED devices.The compound 2 is the second case of single-phase white light MOFs,which can also selectively adsorb the dye molecule methylene blue(MB),and the selection rate of methyl orange was up to 29.7:1.0.The compound 3 was first discovered porous Cd(? found a rare MOFs plane square structure.The compound 4,was the first by[Mn2(COO)2]build units with different Mn-carboxylic chain to construct a three-dimensional framework structure.The compound 5 was given based on self-assembled metal ligand chain pillar a new instance of the constructional column layer framework.The compound 6 was a porous MOFs based on Zn2 cluster unit,with one-dimensional circular holes and two different types of holes of draw-length cage.In situ synthesized compounds[Cu4(btc)(CN)](8),Thermal analysis,IR,Element analysis confirmed the existence of CN'.2.Based on single ligand and mixed ligand,utilized 5-NH2-bdc or 5-Br-bdc,five MOFs were successfully constructed:[Pb(Br-dc)]·DMF(9),Co1.5(Br-bdc)1.5(DMF)]·DMF(10),Co2(Brbdc)2(DMF)2(H2O)]·DMF(11),Cd(Br-bdc)]·2H2O(12),Cu(NH2-bdc)(H2O)](13),[Cd(NH2-bdc)(pz)0.5(H2O)]·2H2O(14,pz=pyridine).Compound 9 has one-dimensional channels and emits bright yellow-green fluorescence at 395 nm excitation wavelength.Fluorescence sensing and identification of Cr(?)(Cr2O72-,CrO42-)and Fe3+ were performed in aqueous solution.LOD of 9 for Cr2O72-,CrO42-and Fe3+were calculated 4.33×10-6mol·L-1,9.19×10-6 mol·L-1,6.60×10-6 mol·L-1,respectively.The potential application value of compound 9 as a fluorescence sensor was confirmed.The solventhermal reaction of NH2-bdc or Br-bdc with Co(?),Cd(?),Cu(?)and Zn(?)ions produced two-dimensional layered MOF,in which four cases of single or mixed ligand MOFs were obtained.Compound 13 of layered two-dimensional(4,4)connection network was further developed by the expansion of the ditopicligands.Compound 14 in a two-dimensional network structure with one-dimensional channels in axis direction,the construction strategy of mixed ligands is realized through the ligand connection of two ligands.3.Investigated linear carboxylate ligand 2',5'-dimethylterphenyl-4,4"-dicarboxylate(H2tpdc).Based on linear carboxylate ligand,series of Cd-MOFs were successfully constructed under solventhermal reaction.The interpenetration regulation effect of reaction temperature or solvent was studied.[Cd(H2tpdc)]·3DMF(15)was the fivefold interpenetrating still reached 57.5%high void volume of with sql network was synthesized.Temperture or sovlent controlled assembly of[Cd(H2tpdc)(DMF)]-DMF(16)and[Cd4(OH)2(H2tpdc)3]·3CH3CN(17)was realized structure controlle.In addition,based on the same reaction material and condition,introduced different metals Mn and La synthesized[Mn4(OH)2(H2tpdc)3]-CH3CN(18)and[La2(H2tpdc)3(H2O)2]·2CH3CN(19).4.Utilized triangle ligand 1,3,5-tri(4-carboxyphenyl)benzene two cases MOFs:[Me2NH2]6[Cd3(btb)4]·10DMF(20)and[Me2NH2][Cd(btb)]·3DMF(21)were successfully constructed under solvothermal conditions.Compound 20 was a single node connected with high void volume of 76.2%.Compound 21 the Cd-based two fold interpenet(3,6)connection MOFs ith a pore volume of 64.8%,In addition,Based on H3btb and H2bdc the mixed ligand strategy,synthesized two cases novel MOFs:[Me2NH2][Mn 1.5(btb)(bdc)0.5]·4DMF-2MeOH(22),[Co2(btb)(bdc)0.5(H2O)]·3DMF·2H2O(23).Compound 22 was a porous MOFs with one-dimensional circular channels based on the[Mn3]unit as the node,with a pore volume of 60.9%.Compound 23 was a 3D porous MOFs based on the[CO2]unit as the vertex,with a pore volume of 55.7%.The frame of compound 22 was dynamic and gate-opening effect was observed in gas adsorption.Compound 20?22?23 exhibited significant Fe(?),Co(?),Ni(?)and Cu(?)substitutions.After Fe(?)and Cu(?)ions were replaced,the monocrystalline properties were significantly maintained and the framework stability was significantly improved. |
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