Three new europium complexes, Eu(PFBA)s (H2O)4, Eu(PFBA)aPhen(H2O)3 and Eu(PFBA)3TPPO(H2O)3,were synthesized using 4-(4-pyridyl formoxyl) benzoic acid (HPFBA), 1,10-phenanthroline (phen) and triphenyl phosphine oxide(TPPO) as the ligands. In the complexes, two characteristic absorption bands of HPFBA due to Vo-H (3 000-2 200 em-1 ) and v c-o (1 697 em-1 ) disappear, the asymmetry stretching vibration vas(coo- ) and symmetry stretching vibration Vs(coo-) of earboxyl appear, and the Δv(vas(coo)-Vs(coo-) ) values are all smaller than that of NaPFBA. The earboxyl group of the ligand HPFBA is dehydrogenated and coordinated to Eu3+ with a bidentate chelating mode. The fluorescence properties of the complexes were studied. Each complex shows five emission bands at about 583,596,618, 655 and 703 nm, which are assigned to the characteristie emission 5 D0-7 FJ (J = 0, 1, 2, 3, 4) transitions of Eus+ , respectively. The fluorescence intensity becomes stronger after the addition of phen and TPPO, and TPPO is better, which is due to synergistic effect of the second ligands.%以Eu3+为中心离子,4-(4-吡啶甲酰基)苯甲酸(HPFBA)、1,10-菲罗啉(Phen)和三苯基氧膦(TPPO)为配体,合成了新型配合物Eu(PFBA)3(H2O)4,Eu(PFBA)3Phen(H2O)3和Eu(PFBA)3TPPO(H2O)3(PFBA=4-(4-吡啶甲酰基)苯甲酸根).红外光谱表明,形成配合物后,HPFBA中羧基位于3 000～2 200cm-1处的羟基伸缩振动峰vo-H和1 697cm-1处的羰基伸缩振动峰v c-o消失,同时,在约1 545 cm-1处出现了羧基反对称伸缩振动吸收峰vas(-coo-),约1 415cm-1处出现了羧基对称伸缩振动吸收峰vs(-coo-),且△v(vas(-coo-)-vs(-coo-))值与HPFBA钠盐相比明显减小,表明配体HPFBA以羧酸根的形式与Eu3+呈螯合双齿配位方式.室温下测定了配合物的荧光光谱,研究了它们的荧光性能.结果表明,配合物均在583,596,618,655和703 nm附近产生五条谱带,为Eu3+的特征发射,分别归属为5D0→7Fj(J=0,1,2,3,4)能级间的跃迁,其中以618 nm附近5D0→7F2能级间的跃迁最强;第二配体Phen和TPPO对Eu3+的荧光发射有明显增强作用,且TPPO效果更佳.
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