【作者】 王丹；

【导师】 李斌；

【作者基本信息】 东北师范大学 ， 无机化学， 2010， 硕士

【摘要】 稀土配合物具有高的发光效率,窄的发射谱线及较长的荧光寿命等优点,过渡金属Ru(II)的配合物也具有稳定的光化学、光物理性质、高的热稳定性、较长的发光寿命等。但其较差的光化学稳定性使其潜在价值不能充分发挥。通常稀土和过渡金属配合物需固定在一种有效的载体中才能进一步改进上述不足和提高已有的优良性能。介孔分子筛具有大的比表面积、规则的孔道结构和良好的热稳定性,将稀土配合物和Ru(II)的配合物与介孔分子筛相结合,可有效改善配合物的光稳定性,提高发光效率,获得优良性能的pH传感器。本论文针对以上问题开展如下工作:(一)研究如何通过Si-CH2共价键把Eu(III)配合物共价嫁接到介孔杂化材料MCM-41的骨架上,提高稳定性和发光性能。由此合成了有机配体2-(4’-羟基苯)咪唑[4,5-f]-1,10-邻菲啰啉，通过对其进行有机修饰，合成了可水解的有机改性硅酸酯的衍生物，使其不但能够和稀土金属Eu(III)配位,而且能够与正硅酸乙酯一起进行水解和共缩聚反应制备共价嫁接的有机-无机杂化材料Eu-MCM-41。系统地研究了共价嫁接配合物Eu-MCM-41的结构、激发态寿命和光稳定性,通过对比可知共价嫁接样品具有比物理包埋和纯配合物更好的光稳定性,另外通过共价嫁接方法,有效地解决了稀土配合物漏析问题。(二)通过水解共缩聚反应将过渡金属Ru(II)配合物共价嫁接至分子筛MCM–41骨架上。我们在氧气传感性能研究的基础上,研究了其pH光学传感性能。由于MCM–41独特的孔道结构,共价嫁接Ru-MCM-41配合物发光强度随着pH增大逐渐降低,展示了良好的pH传感性能。所获得的pH传感介孔材料的性能可以通过改善载体的微相结构进一步提高,为其在生物传感领域的应用提供了可能。更多还原

【Abstract】 Rare earth (RE) complexes have been well known to give sharp, intense emission lines upon ultraviolet light irradiation because the effective intramolecular energy transfers from the coordinated ligands to the luminescent central lanthanide ions, which in turn undergoes the corresponding radiative emitting process. Ruthenium(II) complexes also have stable photophysical property and high thermal stability. However, poor photostability limits their practical application. Recently, because their photophysical properties could be modified by interaction of the host structure, the luminescence properties of RE complexes and Ruthenium(II) complexes supported on a solid matrix were studied extensively. Among them, the mesoporous molecular sieves used as a support for RE complexes and Ruthenium(II) complexes have attracted particular attention.In this paper, the dissertation is focused on the preparation and characterization of various silica-based mesoporous hybrid materials covalently grafted with Eu(III) complex. Detailed analyses on the matrix structure, stability, and photostability of the final obtained mesoporous hybrid materials are investigated. We have designed and synthesized the 2-phenyl-1H-imidazo [4,5-f] [1,10]phenanthroline functionalized hydrolysable compounds with double functions, i.e., as the second ligand of Eu(III) complexe and as the precursor of the sol-gel process. The covalently-grafting of the organic components to the inorganic framework can be achieved via the hydrolyzation and co-condensation reactions between the TEOS and the as-synthesized compounds. The photostability of the Eu-MCM-41 is superior to those of the pure europium complex and that physically incorporated in MCM-41.On the basis of oxygen sensing materials consisted of Ruthenium(II) complexes covalently grafted to mesostructured MCM-41, we also studied its pH senstive fluorescent behavior. The applicability of the principle of direct of covalently-grafting mesoporous material in the development of pH luminescent chemical sensing materials is decreased with the increasing pH. The pH sensing properties of this kind of covalently-grafted functionalized mesoporous powder materials can be further improved via changing the miscrostructure of the supports.更多还原