| Under the guidance of designed synthesis,the work focused on studying the copper-base and silver-based coordination polymers,including synthetic conditions,crystal structure,luminescence properties and applications.Choosing nitrogen heterocyclic and aromatic carboxylic acid as organic ligands,21 novel coordination polymers have been synthesized by hydro?solvo?thermally method,with the structure from mononuclear,single molecular cage to one-dimensional single,double chain,triple chain to two-dimensional layer to three-dimensional framework,and characterized by IR spectra,single crystal and X-ray diffraction.In order to understand how subtle structural changes modulate the luminescence features,the luminescent properties of the coordination polymers in the solid?solvent?state were investigated to elucidate the mechanism of enhanced luminescence and further reveal the structure-property relationship.A series of copper coordination polymers formulated as [?Cu8I8??Cu6I6?0.5?DABCO?3·2H2O]n?1?,[?Cu4I8??DABCO?2·6H2O]2n?2?,[Cu3I3?bib?1.5]n?3?,[Cu4I4?bix?2]n?4?,[Cu?tpp?]2n?5?have been synthesized under solvothermal condition using 1,4-diazabicyclo [2.2.2] octane?DABCO?,1,4-bis?1-imidazoly?benzene?bib?,1,4-bis?imidazol-1-ylmethyl?benzene?bix?and 1-?4-tetrazol-5''-yl?benzyl-3-?pyraziny-l?pyrazole?Htpp?.1 consists of mixed Cu6I6 and Cu8I8,2 exhibits a 2D cuprous iodide layer.The band gap of 4 is 1.98 eV,which displays semiconductor property.3 and 4 demonstrate stronger and longer liftime yellow luminescence emission.When dopping with poly?methyl mathacrylate??PMMA?,the luminescent intensity of 4–PMMA increased 26-fold in comparsion with 4,and 3–PMMA reveals a significant increase of 100 °C in comparison with 3.The luminescent properties of 5 well dispersed in different solvents,which demonstrate distinct solvent-dependent luminescent spectra with emission intensities that are quenched by acetone?detection limit: 14.52 mmol/L?.In the following research,two novel complexes zero-dimensional [Ag?ibz??Hibz?]2?6??Hibz = 4-?1H-imidazolyl?benzoic acid?and two-dimensional [Ag?imbz??Himbz?]n?7??Himbz = 4-?1H-imidazolyl-1-methyl?benzoic acid?have been synthesized by using imidazole carboxylic acid ligand.Through introducing the flexible –CH2–,the distance between two aromatic rings in the ligand is controlled to get different dimensional complexes.7 shows tunable luminescence by changing the temperature.Considering the number of carboxylic acid,three one-dimensional Ag?I?and Cu?I?coordination polymers,formulated as [Ag?2,3-Hqldc?])n?8?,[Ag?3-qlc?]2n?9?and [CuI?3-Hqlc?]n?10?based on ligand quinoline-2,3-dicarboxylic acid?H?2qldc)were synthesized.In order to design higher dimensional coordination polymers,the auxiliary ligands play important roles in the connectivity of multidimensional net.Three novel coordination polymers,namely,[Ag?2,4?-Hpdc??bpy?])n?11?,[Ag?2,2?-Hpdc??bpy?0.5]n?12?,[Cu?2,2?-Hpdc?2?bib?]n?13?[2,4?-H2 pdc = 2,4?-biphenyldicarboxylic acid;2,2?-H2 pdc = 2,2?-biphenyldicarboxylic acid;bpy = 4,4?-bipyridine;bib = 1,4-bis?1-imidazoly?benzene] have been hydrothermally synthesized by mixed ligands.The crystal structures of these coordination polymers indicate that hydrogen bonding and ?···? stacking interactions play critical roles in the formation of the extended supramolecular array.10 shows tunable luminescence at 298 K and 77 K with the large red-shift of 70 nm and the emission shifts from bright yellow to red,indicating thermochromic luminescence.More significantly,11 shows excellent selectivity,fast detection time?< 5 min?,and high sensitivity?detection limit,9.63 nmol/L?for Hg2+ ions in aqueous solution due to a great enhancement of 11-luminescence,which can be attributed to binding Hg2+ cation by non-coordinated carboxyl group efficiently.Job's plot and Benesi-Hildebrand equation indicate the bind ratio is 1:1.Focused on increasing the number of carboxylic acid,3-?2?,3?-dicarboxylphenoxy?benzonic acid?3,2?,3?-H3dpob?and 3-?3?,4?-dicarboxylphenoxy?benzonic acid?3,3?,4?-H3dpob?as main ligands,bpy and bib as auxiliary ligands,six coordination polymers were prepared,formulated as [Ag3?3,2?,3?-dpob??bpy?]n?14?,[Cu4?dpob?2?bpy?2?H2O?]n?15?,[Ag?3,3?,4?-H2dpob??bpy?]n?16?,[Ag3?3,2?,3?-Hdpob??3,2?,3?-H2dpob??bib?3·2H2O]n?17?,[Cu?3,2?,3?-Hdpob??bib?·2H2O]n?18?,[Cu?H2dpob??bpy?]2n?19?.With the help of ascorbic acid as reductant,an exceedingly rare example of visible single-crystal-to-single-crystal from 15 to 19 has been observed by eyes in 3 h.In addition,the emission spectra intensity of 19 is more than four times higher than that of 15.Meanwhile,14 and 17 endow eminent semiconductor property based on Ag···Ag interaction.16 and 17 possess better coplanarity by hydrogen bonding,and display excellent AIE properties.The introduction of 1,3,5-tris?4-carbonylphenyloxy?-benzene?H?3TCPB),bearing C)3 rotating shaft,we successfully construct a pair of complexes [Cu3?TCPB?2?H2O?)3]·2H)2O?20?,{[Cu)2?TCPB??DMA??H2O?]·H2O}n?21?.With changing the ligand torsion angle,20 and 21 possess different trinuclear units,equilateral triangle shaped [Cu3?CO2?3] and linear {Cu3?CO2?2?H2O?2},respectively.Owing to large voids in the framework,20 shows fast response for absorption CV and release CV.Amazingly,20 can also separate CV from MO & CV mixed aqueous solution with fast response and high sensitivity?< 16.13 s?. |
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