Synthesis And Photoluminescence Of Eu/MCM-41 Ordered Mesoporous Composite Material

Rare earth complexs has attracted considerable attention owing to their excellent optical properties. Unfortunately, they have been excluded from application as phosphors because of the poor thermal, photochemical and mechanical stability. One of the methods for applying these organic substances as optical elements in optoelectronic and photonic devices is to fix them in inorganic hosts so that the optical functions might be stabilized. In this paper, MCM-41 mesoporous molecular sieve was chosen as a host for rare earth complexes. And the purpose is to investigate whether MCM-41 mesoporous material is suitable as a host for organic luminescent substances to solve the problems in the application of the latter. Moreover, the work is beneficial for the development of the host-guest chemistry. This paper consists of the following seven chapters:1. The pure mesoporous silica MCM-41 was prepared via the hydrothermal treatment in basic medium. The characteristics of samples were investigated using XRD, HRTEM, N2 adsorption technique and so on, and it was shown that mesoporous silica MCM-41 had been synthesized in this work with uniformly sized pores and long-distance ordered arrangement of hexagonal structure.2. Europium oxide nanoclusters were synthesized within ordered meso porous MCM-41 by using wet impregnation technique. The results showed that the nanoclusters of europium oxide could be successfully confined and distributed into the pores of MCM-41, and pore channels could be destroyed with the introduction of- europium oxide nanoclusters. Simultaneously, the intensity of fluorescence at 613nm, which is still very weak, was reinforced with the increment of europium oxide nanoclusters in the pores.3. The synthesis of Eu(DBM)3phen/APTES-MCM-41 provides a convenient approach of tailoring the surface properties of mesoporous silicates via organic functionalization. The incorporation of the Eu chelate promotes a contraction ofthe structure verified through the decreasing of the distance between pore centers of the hexagonal structure and of order degree; in the meanwhile, the particular mesoporous system can improve the thermal stability of Eu chelate complex. In addition, because the anchored amine of the APTES-MCM-41 has a great effect on the complex field, which surrounds the Eu + ion due to the symmetry of the complex sharply increase. So, compared with that of the Eu(DBM)3phen, the photoluminescent purity of Eu(DBM)3phen/MCM-41 (APTES-MCM-41) is increased.