钇(Ⅲ)、铽(Ⅲ)、铒(Ⅲ)对氨基苯甲酸配合物共掺杂二氧化硅的光声光谱研究

合成了Tb(p-ABA)3·H2O和Ln(p-ABA)3·H2O(p-ABA:对氨基苯甲酸,Ln:Y或Er)配合物共掺杂的SiO2样品.荧光光谱测定结果表明,Y(p-ABA)3·H2O的引入增强了样品中Tb3+离子的特征发光,而Er(p-ABA)3·H2O的引入使Tb3+的发光减弱.光声光谱结果表明,与Tb3+配合物单掺的样品相比,Tb3+和Y3+配合物共掺样品的光声强度降低;而Tb3+和Er3+配合物共掺的样品则情况相反.实验测定了共掺杂样品的相对量子发光效率和发光寿命,从无辐射跃迁和辐射跃迁的角度提出共发光效应可能的机制.结合对室温下陈化干燥样品的分析发现,只有经适当的热处理过程才能在SiO2凝胶中形成具有多核结构的稀土配合物.

Photoacoustic Study of Y3+, Tb3+ and Er3+ Complexes with Aminobenzoic Acid Co-doped Silica Samples

Lanthanide complexes Tb(p-ABA)3·H2O and Ln(p-ABA)3·H2O(p-ABA=p-aminobenzoic acid; Ln =Y or Er) co-doped silica samples were prepared. It was found that the characteristic emissions of Tb3+ in the silica samples increase with the addition of Y(p-ABA)3·H2O, while the reverse is true with the addition of Er(p-ABA)3·H2O. Compared with only Tb3+ complex doped silica sample, the photoacoustic intensity in the region of the ligand absorption decreases for Tb3+ and Y3+ complexes co-doped sample, and increases for Tb3+ and Er3+ complexes co-doped sample. The relative luminescence quantum yields and lifetime for the co-doped samples were determined, and the possible mechanism for the co-luminescence phenomena was interpreted from two aspects: radiative and nonradiative processes. Lanthanide complexes doped wet silica gels, which have undergone aging and drying at room temperature only, were also studied. The results indicate that p-ABA does not coordinate with the lanthanide ions in the silica gels without a suitable heat treatment. The co-luminescence effect found in this work will contribute the better design of new type of luminescence materials.