摘要:为了得到粒径均匀的纳米稀土铕四元配合物,采用化学沉淀法,进一步优化试验条件,制备 Eu(BA)(TTA)2 邻菲罗林纳米微晶,采用元素分析、红外光谱、热重分析、荧光光谱和透射电镜等方法对其进行表征和分析。 结果表明,稀土铕四元配合物中高效率的能量传递是通过在 2 种不同第一配体之间形成的“协同效应”来完成,四元配合物中 3 种不同的配体可以更好地取代配位水;四元稀土配合物不仅发光性能优于常见的三元配合物,而且热稳定性好,粒径较小且均匀,可进一步掺入 高分子形成功能性含稀土高分子聚合物;选用合适的缓冲溶液,在调节 pH 时将缓冲溶液缓慢地逐滴加入,可采取往反应体系中通氨气的方法,以使体系的 pH 改变较为平稳,生成的沉淀粒径较小且均匀。
关键词:稀土配合物;铕;纳米微晶;发光性能
Abstract:To obtain the nano-sized europium quaternary rare earth complexes with uniform particle size, the way of chemical precipitation was adopted and the experimental conditions were optimized to prepare Eu(BA)(TTA)2 phenanthroline hydrate nano-crystallines. The methods of elemental analysis,IR,TG,fluorescence spectroscopy and TEM were utilized to characterize and analysis them. The results show that the high efficiency energy transport in europium quaternary rare earth complexes is accomplished by the “synergistic effect” formed between two different first ligands. Three different ligands in quaternary complexes can replace coordination water better. The quaternary rare-earth complexes are not only better than common ternary complexes on light-emitting performance,but also have better thermal stability, smaller particle sizes and uniformity. They can be further mixed with the polymer to form a functional rare earth polymer. Appropriate buffer solution should be chosen. When regulate pH,the buffer solution should be dropped drop bydrop slowly. The method of ventilate ammonia into the reactive system can even be adopted to make the change of system pH more stable and the particle sizes of the formed precipitations are small and uniform.
Keywords:rare earth complexes;europium;nano-crystalline;light emitting property