Studies On SBA-15 Host-Rhodamine B Guest Nanocomposite Material And Phenylating SBA-15 Material

Mesoporous SBA-15 molecular sieve possesses many characterisitcs such as easy preparation, periodic hexagonal channel, tailoring of pore dimension, very high surface area and facile modification of surface. There are more obvious advantages for the SBA-15 compared with other mesoporous molecular sieves because the SBA-15 has higher thermal stability and hydrothermal stability, larger pores, thicker walls and a lot of micro- and narrow mesopores that coexist with the regular hexagonal framework of main channels. Because of the above numerous advantages, the mesoporous molecular sieve SBA-15 synthesized by using triblock copolymers as structure directing agents as well as its correlative materials are becoming one of the research focuses in recent years. The studies of this thesis include the following two parts:The first part is as follows: the mesoporous material SBA-15 was prepared under a strong acidic condition by using triblock copolymer poly(ethylene glycol)- block-poly (propylene glycol)-block- poly(ethylene glycol) as template. The host-gust nanocomposite material (SBA-15)-RhB was prepared by embedding orgainic laser dye rhodamine B(RhB) into the pores of the SBA-15 by liquid grafting method. By means of chemical analysis, powder X-ray diffraction,Fourier transform infrared spectroscopy,low-temperature nitrogen adsorption-desorption technique, solid state diffuse reflectance absorption spectroscopy, transmission electron microscopy, scanning electron microscopy and luminescence studies, the host-gust nanocomposite material was characterized. The results showed that the guest molecules were sucessfully encapsulated in the channels of the SBA-15 molecular sieve and the frameworks of the molecular sieve in the prepared composite materials did not collapse. The host-gust composite material possesses good luminescence property and it is hopeful to get application in the field of laser.The second part is as follows: phenylation mesoporous molecular sieve of SBA-15 [Ph-(SBA-15)] was synthesized by post-synthesis method using phenyltriethoxysilane as coupling agent. The product was characterized by means of element analysis, powder X-ray diffraction, Fourier transform infrared spectroscopy, low-temperature nitrogen adsorption- desorption technique, transmission electron microscopy, thermogravimetry-differential thermal analysis methods. The results showed that phenyl was successfully grafted to the mesoporous molecular sieve SBA-15. The Ph-(SBA-15) mesoporous molecular sieve still retained ordered mesoporous structure and possesses high thermal stability.