| Mesoporous materials have many potential applications in catalysis, sorption, bio-molecule separation and controlled synthesis of nanostructures on size and dimension due to their large specific surface area, large pore volume, uniform pore size, controllable morphology, and easily functionalized surface. The research on mesoporous materials is currently changing to the exploitation of their applications; however, the applications of mesoporous materials in the large bio-molecule separation and the nanostructure fabrication are just at the beginning. In this thesis, we focused on the applications of SBA-15 in the separation of large bio-molecules and the controllable synthesis and assembly of nanomaterials and the related fields as our research directions, which have great theoretical and practical significations and relate to several hot fields including life science, nano- science and technology and mesoporous materials science. The main contents of our work are summarized as follows. In Chapter 2, we reported the synthesis of uniform SBA-15 mesoporous materials with sphere-like morphology by adjusting the synthetic conditions and the succedent functionalization of their surface for the liquid chromatogram separation. With C18-modified SBA-15 (C18-SBA-15) as the substrate for high performance liquid chromatogram, we succeeded in separating many bio-molecules with different molecular weights, including small bio-molecules (cysteine, glutathione, 6-thiopurine and dopamine), peptides (the peptides of the myoglobin and bovine serum albumin digested by trypsin) and proteins (lysozyme, bovine serum albumin, myoglobin and ovalbumin. Compared with the commercial substrates, C18-SBA-15 exhibits better separative effect, higher plate number, higher resolution, and it also shows a good separation repeatability, initially confirming the application foreground of SBA-15 in liquid chromatogram. In addition, we also examined the adsorption and desorption ability of SBA-15 for proteins. By adjusting the pore size of SBA-15 and modifying the surface of SBA-15 with different functional groups, we realized the separation of proteins with different molecular weights. In Chapter 3, we proposed an in-situ adsorption technique combined with the functionalization of SBA-15 surface with thiohydroxy (-SH), the adsorption of Pb2+ to thiohydroxy, and the decomposition of the Pb-SH complex under certain conditions to form uniform binary metal sulfide PbS nanocrystals (6 nm) dispersed in SBA-15 mesoporous channels. The main advantage of this method is the introduction of two types of ions under un-reactive conditions, which effectively resolves the channel obstruction problem by traditional dipping technique. Furthermore, by changing the pore size of SBA-15 template, the nanocrystals' size can be successfully controlled in the mesochannels. This method can also be extended to the synthesis of other binary sulfide nanocrystals such as CdS nanocrystals.In Chapter 4, we developed the in-situ adsorption method and made a success in the synthesis of binary sulfide nanowires inside the mesochannels of SBA-15 by changing the experimental conditions. The key to synthesize nanowires instead of nanoparticles in the mesochannels by in-situ adsorption method is to increase the amount of inorganic materials introduced into the mesochannels. In this chapter, we substituted alcohol-extraction method for the calcination process to remove the surfactant used in the synthesis of mesoporous materials. The alcohol-extraction method to remove the surfactantbasically avoid the lose of the amount of hydroxy during calcination process and then keep more hydroxy on the mesoporous material' surface, which leads to introduce more amount of the functionalized -SH and then the metal ions into the mesochannels. The decomposition of metal-SH complex with high amount results in the formation of nanowires in the mesochannels finally. By this method, we synthesized PbS nanowires with uniform diameter (6 nm) at first, and then extended it to the synthesis of...
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