Synthesis, Structure and Spectroscopic Properties of La-doped Europium Luminescent Materials

Five new La-doped europium complexes with 2-hydroxy -6-methylnicotinic acid(HA) and 1, 10-phenanthroline(phen) as ligand were synthesized and characterized by elemental analysis, FT-IR spectra and fluorometric analysis. The results show that the composition of the complexes was confirmed to be (EuxLay)A3phen·3H2O (x∶y=0.10∶0.90, 0.30∶0.70, 0.50∶0.50, 0.70∶0.30, 0.90∶0.10), and carboxyl of the ligand chelated with rare earth ions in chelating bidentate form. Lanthanum had an accumulative effect on europium complexes, which rose with the increase of lanthanum ions concentration. The measured fluorescence lifetime of five complexes were very similar and around 1 ms.