Synthesis and Characteristic Study on Complexes of Europium(III) and Maleic Acid Doped with Non-Fluorescent Ions

Complex of europium (III) with maleic acid, and binuclear complexes of europium(III)with maleic acid doped with non-fluorescent ions gadolinium, lanthanum and yttrium, were synthesized. The compositions and structures of complexes were characterized with elemental analysis, single crystal X-ray diffraction, IR and DSC-TG. Fluorescent properties were studied with fluorescence spectrum. The results indicated that the strongest fluorescent complexes were obtained when the ratio of europium and non-fluorescent ion was 8:2. The order of Eu³⁺ fluorescence strengthened by three doped rare earths was Gd³⁺ > La³⁺ > Y³⁺.