Photocatalytic Of Titanium Dioxide: Flouride-doped And Mesoporous Structure

Environmental issues are among the biggest challenges in the 21st century, with problems related to hazardous waste remediation emerged as a high international priority. As the representative of advanced oxidation technology, photocatalytic degradation of organic compounds over TiO2 has been extensively studied as a potential technology for water treatment and air purification. By using abundant solar light and molecular oxygen as driving force, a variety of organic pollutants can be degraded, and/or mineralized into CO2 over irradiated TiO2 at ambient temperature and pressure. However, the efficiency of TiO2 photocatalysis achieved so far is still low for practical application, mainly due to fast recombination of the charge carriers.This thesis focused on the intrinsic mechanism of TiO2 photocatalysis, and catalysts with high activity were designed via fluorine-doped and the mesoporous morphology. A relatively systematic investigation was accomplished about the basic principle and factors of photocatalysis. In this thesis, results were also gained valuable in both academic discipline and practical application.(1) This article compares the fluoride ion-doped bulk and surface adsorption of TiO2 photocatalytic degradation of organic matter influence, compared to the TiO2 photocatalytic process to promote the role of bulk-doped fluoride ion is greater than the surface adsorption of fluoride ion. while at the catalyst surface double layer is greater than the outer surface of the fluoride ion adsorption of fluoride ions, which coincided with our previous assumptions are consistent. in addition, this study also showed that if the increase in O2 concentration on the catalyst surface, and or by fluorine-doped fluoride ion external to join, will be able to discover the original TiO2 photocatalytic activity significantly improve the quantum efficiency of the photocatalytic system.(2) Use template method successfully synthesized mesoporous structure with anatase TiO2. Study the synthesis process of mesoporous TiO2 titanium source morphology, organic solvents, solvent evaporation of humidity and temperature and other factors. And with different temperature calcined mesoporous TiO2 for degradation of phenol, chlorophenol. and found well-preserved mesoporous structure of the photocatalytic activity of TiO2 has a huge positive effect.