Syntheses And Properties Of Lanthanide Compounds Constructed From Nitrogen Heterocyclic Carboxylic Acids And Polyoxometalates

Polyoxometalates,as inorganic ligands with excellent physicochemical properties,are widely used in catalysis,adsorption and other fields.In this work,eight lanthanide metal organic compounds were synthesized by hydrothermal synthesis based on Keggin type polyacid and 2,2’-bipyridyl-6,6’-dicarboxylic acid（H2L¹）as organic ligand:Pr₄（L¹）₄（H₂O）₁₀SiMo₁₂O₄₀·3H₂O（1）;Pr₄（L¹）₄（H₂O）₁₀SiW₁₂O₄₀·3H₂O（2）;Nd₄（L¹）₄（H₂O）₁₀SiW₁₂O₄₀·3H₂O（3）;Ce₄（L¹）₄（H₂O）₁₀SiW₁₂O₄₀·3H₂O（4）;Ce₄（L¹）₄（H₂O）₁₀SiMo₁₂O₄₀·3H₂O（5）;La₄（L¹）₄（H₂O）₁₁PW₁₂O₄₀·2H₂O（6）;Eu₄（L¹）₄（H₂O）₈SiW₁₂O₄₀·4H₂O（7）;Eu₄（L¹）₄（H₂O）₈SiMo₁₂O₄₀·5H₂O（8）;A silver organic compound was synthesized with 5-（2-pyridine）-1H-tetrazole（L²）as organic ligand:[Ag₂（L²）₂]n（9）;In the structure of 1-8,rare earth metal ions coordinate with L¹ to form a 2D layered structure.Keggin-type polyoxometalates anions fill between two lanthanide metal organic layers,and are connected with the lanthanide metal organic layers by hydrogen bonding interactions to form a three-dimensional supramolecular network structure.The Ag ions in 9 are interconnected with organic ligands to form a 1D chain structure with continuous pore structure.The 1D chain is connected to form a 3D supramolecular structure by hydrogen bonding and π…π stacking.Among them,the fluorescence properties of 4-6 and 9 are better.1-8 show electrochemical behavior,1 can electrocatalytically reduce nitrite ions,5 can electrocatalytically oxidize ascorbic acid.The experimental results of photocatalytic degradation of organic dyes and adsorption removal of organic dyes show that 1-8 can remove organic dyes（MB,RhB）.9 has good bacteriostatic ability and can be used as a potential solid bacteriostatic agent.