| In this paper,for the purpose of design and preparation of molecular materialtransition metal-organic coordination polymer with photoelectric-electric conversion function,two series of coordination polymers were designed and synthesized by hydrothermal method:(1)With 4,4'-dipyridylamine which has rigid conjugated N-heterocycle and flexible bendable imine group as the structural constructing ligands,inorganic small molecules and flexibl/rigid organic carboxylic acid molecules as cooperative ligands,design and synthesize series of coordination polymers(1-8);(2)With 1H-1,2,3-benzotriazole-5-carboxyl(H2btca)as building blocks and functional ligands together with 2,2'-bipy and phen molecules as the auxiliary functional ligands,design and synthesize series polymers(9-13).Their structures were determined by X-ray single crystal diffraction,and their molecular formulas are as following:(1)[Co Zn(OH)(dpa)(trans-C4H2O4)1.5]n(2)[Co(dpa)Cl2]n(3){[Co2(dpa)2(suc)2]ˇH2O}n(4)[Co(dpa)(1,4-bdc)]n(5)[Co(Hdpa)2(SO4)2(H2O)2]ˇ4H2O(6)[Co2(Hdpa)2(ox)(SO4)2(H2O)4](7){[Co Ni(dpa)(mal)2(H2O)2]ˇ2H2O}n(8){[Cu5(dpa)2(suc)2(OH)4(SO4)]ˇ2H2O}n(9){[Co3(btca)2(OH)2]ˇ2H2O}n(10)[Co(bcta)(2,2'-bipy)]n(11)[Fe(btca)(phen)]n(12)[Zn(btca)(phen)]n(13)[Co(btca)(phen)]n(trans-C4H2O4=fumaric acid,suc=succinic acid,1,4-bdc=p-phthalic acid,ox=oxalic acid,mal=malonic acid,2,2'-bipy=2,2'-Bipyridine,phen=1,10-phenanthroline)Structural analysis shows that in the polymers(1-8),the ligand dpa exhibits two forms of existence and three different coordination modes to form extended structure with different dimensions.In the polymers(9)-(13),the ligand btca2-takes two different coordination modes to bridge the metal ions,and also form different dimensions of the polymers.In polymer(9),the btca2-ligand acts as a penta-dentate ligand bridging metal ions to form 3D infinite structure;In polymer(10)-(13),the btca2-uses tetra-dentate bridging mode to connect metal ions to form 2D infinite structure.The polymers are characterized by IR,UV-Vis-NIR,SPS,FISPS,XRD and TG.Based on the structure,especially the photoelectric properties of each polymer were analyzed.The influence factors of photoelectric performance and structure law are discussed,and the following preliminary results are obtained:[1]There were photovoltage responses in the range of 300?800nm under the inducement of UV-Vis light for thirteen polymers,which indicates they all possess photo-electric conversion properties.Theses polymers exhibit the characteristics of the P-type semiconductors.[2]The 3D infinite structure constructed by the coordination/covalent bond is more favourable to the transmission of photogenerated carriers than that constructed by the hydrogen bonds,which enhances the photovoltaic response intensity of the polymers.[3]The different types of ligands of coordination polymers affect the width of photovoltaic response.Introducing the conjugating ligand into structure of the coordination polymer can make the scope of photovoltaic response to shift into the visible region,i.e.,broadening the absorption of light.Which is very benefit to enhance the conversion efficiency.[4]The valence electronic configuration of the central metal influence photoelectric properties.In polymer(11)-(13),the Fe(II)ion is in a low oxidation state in polymer(11)with strong reducibility and easily being oxidized,presenting the charge transfer transition more easily,Therefore,the SPV response broaden towards the visible region.Above the conclusions can provide an reference for the preparation of new type photoelectric conversion materials. |
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