Synthesis and Photoluminescence Properties of Doped Europium Complexes with 2-Pyrazinecarboxylate

Seven europium complexes of 2-pyrazinecarboxylate (pyca) doped with inert fluorescent lanthanide ions (La3+, Y3+) have been synthesized. Elemental analysis, IR spectroscopy, absorption spectroscopy and TG-DSC analysis showed that the complexes have the formulas of Eu(pyca)(3)center dot 3H(2)O and EuxRE1-x(pyca)(3)center dot 3H(2)O (RE=La, Y; x = 0.7,0.5,0.3), respectively. The lanthanide ions coordinated with carboxylic oxygen atoms and nitrogen atoms of pyca. Luminescence spectra and luminescence life-times of the complexes have been measured and their quantum yields were calculated. The results showed that the existence of La3+ and Y3+ ions could enhance the luminescence intensity and quantum yield of the europium complexes, which may arise from the intramolecular energy transfer between the inert fluorescent lanthanide ions and Eu3+ ion. Those doped complexes have the advantages of strong luminescence, low cost and practical application value.