Designation,Syntheses And Properties Of Coordination Polymers Based On Tetra(triazole)Ligand

Containing triazole ligand coordination polymers as a new functional materials,with interesting topological structure,the structure can be adjusted and controlled,are widely used in gas storage and separation,fluorescent probes,photocatalytic degradation,magnetism,electrochemistry,and other fields.Triazole ligand with multicarboxylate ligands and metal ions can build coordination polymers with unique structure and excellent performance.In this work,the rigid ligand ttpe=1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene was synthesized as the main ligand.Ten coordination polymers were synthesized by the combination of ttpe and multicarboxylate ligands,and a series of characterizations of their structures and properties were characterized.The applications of photocatalytic degradation and fluorescent probes were mainly explored.1.Two coordination polymers {[Co(ttpe)(H2O)2](1,4-bdc)-(1,4-H2bdc)}n(1)and{[Co(ttpe)(H2O)2](Hbtc)·(DMAC)-(H2O)2}n(2)were synthesized by hydrothermal method with ttpe ligand,1,4-H2bdc(1,4-H2bdc=1,4-benzenedicarboxylic acid)and H3btc(H3btc=1,3,5-benzenetricarboxylic acid).They all show a(4,4)-connected binodal two dimensional topology.Network of 1 can capture neutal 1,4-H2bdc molecules and 1,4,bdc2-anions,and network of 2 can capture DMAC molecules and Hbtc2-anions.Coordination polymers 1 and 2 are good photocatalyst for the degradation of methylene blue(MB)and rhodamine B(RhB)under visible-light irradiation.The degradation efficiencies of MB and RhB can reach 91%and 93%,respectively,after 90 min using coordination polymer 2 as catalyst.2.A copper(?)coordination polymer {[Cu4Br(ttpe)3]Br2·(OH)}n(3)was synthesized by the combination of ttpe and metal copper ions.3 exhibits a two-fold interpenetrating(4,12)-connected 3D topology containing the[Cu4Br]tetranuclear copper cluster building block.Its band gap(Eg)is 2.20 eV,which can efficiently degrade organic dyes MB and RhB under visible-light irradiation.The degradation efficiencies are 93%for MB after 90 min and 92%for RhB after 120 min using coordination polymer 3 as catalyst.The mechanism of photocatalytic degradation of organic dyes was explored.3.Three coordination polymers {[Cu(ttpe)0.5(1,3-bdc)]·2H2O·DMAC}n(4),{[Cu(ttpe)0.5(1,3-bda)]·3H2O}n(5)and {[Cu2(ttpe)(bptc)]·6H2O·DMAC}n(6)were synthesized with ttpe ligand,1,3-H2bdc(1,3-H2bdc=1,3-benzenedicarboxylic acid),1,3-H2bda(1,3-H2bda=1,3-benzenediacetic acid)and H4bptc(H4bptc=3,3',4,4'-biphenyltetracarboxylic acid).4 exhibits a(4,4)-connected 2D network,5 exhibits a(3,4)-connected 2D network,6 exhibits a(4,4,4)-connected 3D network.4-6 are semiconducting in nature,with Eg of 2.22 eV(4),2.27 eV(5)and 2.21 eV(6).4-6 are good catalysts for the degradation of organic dyes under visible light irradiation.The degradation efficiencies are 90%for MB after 105 min,90%for RhB after 135 min and 91%for MO after 165 min using coordination polymer 6 as catalyst.4.Two coordination polymers {[Cd(ttpe)(H2O)(1,3-bdc)]·4H2O·DMAC}(7)and{[Cd(ttpe)(1,3-bdc)]·3H2O}n(8)were synthesized with the main ligand ttpe and 1,3-H2bdc at different temperatures.Two cadmium coordination polymers{[Cd4(ttpe)2(1,3-bda)4(H2O)4]·5H2O}n(9)and{[Cd3(ttpe)2(btc)2(H2O)2]·3H2O·DMAC}n(10)were synthesized with ttpe ligand,1,3-H2bda and H3btc.7 exhibits a(4,4)-connected 2D network,8 exhibits a two-fold interpenetrating(3,5)-connected 3D network,9 exhibits a(3,4)-connected 2D network,10 exhibits a(3,4,4,5,5)-connected 3D network.The fluorescence performance of coordination polymers 7-10 were measured.7 is a multi-responsive luminescent sensor for simultaneous detection and sensitivity of Cr2O72-,CrO42-,MnO4-Cu2+,Ag+and Fe3+in aqueous solution.The detection limits are 0.094 ?M for Cr2O72-,0.142?M for CrO42-,1.14 ?M for MnO4-,1.06 ?M for Cu2+,0.352 ?M for Ag+,and 0.124?M for Fe3+.