Synthesis, Characterization And Studies On Fluorescence Properties Of Rare Earth With Phenoxyacetic Acid And 2,4,6-tris-(2-pyridyl)-s-triazine

In this work, four kinds of single-nuclear rare-earth ternary complexes with samarium, europium, terbium and dysprosium as the central ions were synthesized using phenoxyacetic acid as the first ligand,2,4,6-tris-(2-pyridyl)-s-triazine(TPTZ) for the second ligand. We also synthesized europium, terbium, dysprosium and samarium doped with lanthanum, yttrium, gadolinium heteronuclear of rare-earth complexes. Elemental analysis, rare earth coordination titration, inductively coupled plasma atomic emission spectrometry (ICP) measurement and differential thermal-thermogravimetric analysis shows that the complexes have the composition of Eu(POA)3(TPTZ)·3H2O;Tb(POA)3(TPTZ)·3H2O;Sm(POA)3(TPTZ)·3H2O; Dy(POA)3(TPTZ)·3H2O;Eu0.5Ln0.5(POA)3(TPTZ)·3H2O;Tb0.5Ln0.5(POA)3(TPTZ)·3 H2O;Sm0.5Ln0.5(POA)3(TPTZ)·3H2O;Dy0.5Ln0.5(POA)3(TPTZ)·3H2O(Ln=La,Y,Gd). The molar conductivity indicates that all the complexes are non-electrolytes; Infrared spectroscopy shows that the phenoxyacetic acid through the oxygen atoms and 2,4,6-tris-(2-pyridyl)-s-triazine through the three nitrogen atoms coordinate with the rare earth ions,respectively.Fluorescence shows that the fluorescent intensity of terbium complexes is stronger than europium complexes, and fluorescence lifetime shows that europium complexes is longer than terbium complexes; heteronuclear Gd3+-doped rare earth complexes is stronger than Y3+and La3+-doped rare earth complexes,they suggest that the triplet state level of ligands with the excited state of the lowest energy level of Eu3+, Tb3+ match better. In addition, this article further discussed the fluorescence properties of the ligand and ion-doped rare earth complexes, and four molecular structures of complexes.