The Studies On The Assembly Of Mesoporous Material MCM-41 And Luminescent Organic Molecules

There are three parts in this paper: The synthesis of luminescent Alq3-MCM-41 assembly, the organic-inorganic hybrid Eu(BA)₃-MCM-41 assembly, and the assembly of MCM-41 and the fluorescence dyes. The products were characterized by small angle XRD, IR, Excitation-emission spectra and N₂ adsorption-desorption, and the spectra properties were mainly studied.1. Small organic luminescent molecule of 8-hydroxyquinoline aluminum (Alq3) as an active optical guest was incorporated into the one-dimension channels of MCM-41. The results from XRD patterns suggest that the Alq3-MCM-41 also have the typical mesoporous structure, but the channels were partially destroyed by the entrance of Alq3. The appearance of absorption band at 1 542cm-1 shows that there is strong binding force between MCM-41 and Alq3 in the assembly. Alq3-MCM-41 has excellent luminescent property owing to the energy transfer between the host and the guest, which is mainly due to the mutual effect of the hybrid inorganic-organic material.2. Eu(BA)₃ was assemblied into the channels of MCM-41 directly, then the organic-inorganic hybrid material Eu(BA)₃-MCM-41 was gained. The results indicate that the assembly have more ordered mesoporous structure than MCM-41. Eu(BA)₃ can act as a secondary template when it enters the channel and increase the ordered framework of mesoporous silicon. Eu(BA)₃ can be bonded with the hydroxyl in the channel. The relative luminescent intensity of the peak at 610.2nm which belongs to the transition of 5D0→7F2 of Eu³⁺ is up to 2 859.4 in the assembly, and it is 299% times more than that of Eu(BA)₃.3. Luminescent dyes like RhB, Rh6G and the mixture were assemblied with mesoporous material MCM-41, and the assemblies were synthesized. The results show that the assembly remains the hexagonal structure of MCM-41, which reduces in a certain degree as the entrance of the dye molecules. The dyes can be bonded with the hydroxyl of MCM-41, so the assembly exhibits a good fluorescent property. The assembly of mixed dyes has a stronger luminescence than that of single dye.