Synthesis and fluorescent properties in complexes of Eu(III), Tb(III), and Sm(III) with β-diketone and 2,2′-bipyridine

Three new rare earth ternary complexes, RE(PB)3bpy (RE=Sm3+, Eu3+, and Tb3+), were synthesized by the reaction of 1-(p-phenylethynylphenyl)-1,3-butanedione (HPB) and 2,2′-bipyridine (bpy) with rare earth chloride RECl3, respectively, in alcohol solution. The compositions were characterized by means of infrared (IR) spectra, chemical analysis, elemental analysis, and thermodynamic analysis. Luminescent properties of the three complexes were studied. At room temperature, under UV light excitation, the Sm3+, Eu3+, and Tb3+ complexes exhibit characteristic emission of the central ions. The fluorescence spectra show that the fluorescence emission intensity of Eu3+ complex is the strongest. The narrow strongest emission band of Eu3+ complex is considered to be a valuable material with bright red fluorescence.