Abstract
The first section of the thesis is the preparation of carbon-coated titania in benzyl alcohol by using titanium tetrachloride as a titanium source and fructose as a carbon source. The crystallinity of the anatase nanocrystals and the graphitization degree of the carbon coating can be enhanced by the subsequent heat treatment in vacuum. The carbon-coated titania materials exhibit high adsorption amount and fast photodegradation rate for methylene blue. Similar synthesis condition can be applied to prepare titania 3D nanostructures by a seeding growth process. Furthermore, Pt@TiO2 nanocomposites are prepared and applied as anodic catalysts in direct methanol fuel cell. While Pt@TiO2 nanocomposites produce smaller current than commercial catalyst E-TEK (20wt% Pt on Vulcan), they exhibit lower oxidation potential of methanol and carbon monoxide than E-TEK. In the second section, mesoporous silica SBA-15 have been synthesized by using end-group oxidized structure directing agent. Compared to the conventionally prepared SBA-15, the prepared materials have enhanced degree of silica condensation, better hydrothermal stability and additional intra-particle porosities. Besides, foam-like silica mesophases can be synthesized at pH 4. The structural properties of foam-like silica mesophases can be modified by post-synthesis treatments and the surface can be functionalized by direct-cocondensation. Foam-like mesoporous carbon materials can also be synthesized using foam-like silica mesophases as hard templates by nanocasting.