Preparation Of TiO₂/C Hybrid Aerogel At Different Carbonization Temperatures And Study On Their Photocatalytic Properties

In this thesis, the target samples of TiO2/C hybrid aerogel were made by the common modus sol-gel, then dye in wastewater was degraded with the samples under visible light.In the experiment, titanium tetrachloride was selected as the titanium source, resorcinol and furfural as the carbon source, ethanol as solvent, propylene oxide as a network-inducing agent, ethyl acetoacetate as a complexing agent. In order to study how the conditions in preparing process determine the samples’morphology, performance, the gel dried was carbonized by supercritical drying process at different carbon temperature. XRD patterns of the samples showed that in four carbonization temperatures, the samples are all in the presence of TiO2 crystalline phase with anatase, and with the rise of carbonization temperature, the grain size increases, indicating that temperature rise leads to the growth of grains. From TEM images it can be observed that nanoparticles of titanium dioxide uniformly are embedded in a substrate of amorphous carbon formed. BET characterization data shows that sample carbonized at 900℃F has higher specific surface area than those at other temperatures. From UV-Vis diffuse reflectance spectra it can be obtained that TiO2/C hybrid aerogels doped with the carbon does improve its response to visible light, and furthermore significant redshift of sample carbonized at 900℃ appears. Ti peak separation at XPS analysis implys that the sample carbonized at 900℃ may contain Ti3+. Performance tests also show that the samples at 900℃ not only have good absorption properties, but also very good photocatalytic degradation. Finally its degradation mechanism was also discussed.