Dissertation > Excellent graduate degree dissertation topics show

Study on Preparation and Photocatalytic Properties of Co-doped TiO2for Degradation of Methylene Blue

Author: MiaoGuaShuai
Tutor: ZhangHuaRong
School: Henan University
Course: Condensed Matter Physics
Keywords: Photocatalytic materials Titanium dioxide Codoped Methylene blue
Type: Master's thesis
Year: 2013
Downloads: 488
Quote: 0
Read: Download Dissertation


In the first chapter, a brief summary about nano-materials an photocatalytic nano-materials was firstlygiven. Secondly, we analyzed the structure and photocatalytic mechanisms of titanium dioxidephotocatalyst and evaluated the advantages and disadvantageous of titanium dioxide photocatalytic material.Then the main preparation methods of titanium dioxide were introduced. Moreover, the modificationmethods of improving the photocatalytic performance of TiO2were reviewed in details, among whichmodifying TiO2photocatalyst by doping was emphatically described. Finally, the purpose and significanceof this thesis were briefly given.In the second chapter, Iron or iodine single doped and their co-doped TiO2nanocrystalline wereprepared by the sol-gel method and investigated by XRD, XPS, UV-Vis spectrum, respectively. Thephotocatalytic performances of the samples were evaluated by photocatalytic degrading methylene blue.XRD results show that all the samples compose of the anatase phase and the average grain sizes aredifferent from7to15nm. After the dopings, the absorption properties of the samples are significantenhanced. With the increase of Fe doping level, the photocatalytic activities of the codoped samplesincrease and then decrease gradually. The best photocatalytic property is presented in the codoped samplewith0.2%Fe doping level. The mechanisms of the photocatalytic property changes were further discussedby several factors such as grain size, absorption performance and band structure.In the third chapter, undoped, F-doped, Y-doped and (F, Y)-codoped TiO2nanoparticles were preparedby the sol-gel method and investigated by XRD, TEM, XPS, UV-Vis spectrum and PL spectrum,respectively. The photocatalytic properties of the samples were evaluated by photocatalytic degradingmethylene blue. It is found that there is no visible absorbance edge shift after the dopings in TiO2. That is tosay, the absorption performance can not be improved by the doping. With the increase of F doping level,the photocatalytic activity of TiO2are gradually enhanced, resulting in an optimal doping level of10%. TheF doping sites can more easily trap the hydroxyl in the solution, which results in the formation of morehydroxyl radicals, enhancing the photocatalytic activity of the TiO2photocatalyst. In the samples of (F,Y)-codoped TiO2, the photocatalytic property is improved and then depressed with the increase of Y doping level. The best photodegrading efficiency is observed in the sample with0.05%Y doping level. Thephotocatalytic property changes in the codoped sample were interpreted by a competing mechanismbetween the photo-generated charge carrier recombination center and photocatalytic activity center, thedouble-role played by the Y doping induced oxygen vacancy.In the forth chapter, undoped, F-doped, Zn-doped and (F, Zn)-codoped TiO2nanoparticles weresynthesized by the sol-gel method. XRD results reveal that the samples are anatase phase with the grainsize of10-14nm. From the UV-Vis spectra of the samples, it is found that the optical absorption propertyof TiO2can not be obviously improved by the doping. The photocatalytic properties of the samples wereinvestigated by photocatalytic degrading methylene blue. The results show that the codoped sample with2%Zn doping level presents the best photocatalytic performance. Too large or too small zinc doping levelwill reduce the photocatalytic performance of TiO2photocatalyst. The influence mechanisms of Zn dopinglevel on the photocatalytic activity of the codoped TiO2is discussed in details.In the fifth chapter, a series of I-N codoped, single doped TiO2nanoparticles and pure TiO2werefabricated by the sol-gel method. The prepared photocatalytic materials were characterized by XRD,UV-Vis spectrum and photocatalytic activity measurement. XRD showed that all the samples are anatasephase with the grain size distribution of7-12nm; Ultraviolet-visible absorption spectra suggests that thevisible light absorption of the nitrogen doped and codoped samples are significantly enhanced. The bestphotocatalytic property is observed in the sample of1%I-N codoped TiO2by photocatalytic degradation ofmethylene blue experiments. The photocatalytic activity of the N doped TiO2is exactly enhanced by the Idoping.

Related Dissertations

  1. Studies on Synthesis, Characterization and Properties of Fe-V Co-doped TiO2 Catalyst,O614.411
  2. Preparation of One-dimensional Nano TiO2 and Study on the Decolorization of Dyeing Wastewater,TB383.1
  3. Iron, lanthanum -doped nano TiO \u003csub\u003e 2 \u003c/ sub\u003e Preparation and photocatalytic properties,O614.411
  4. Preparation and Photocatalytic Properties of Rare Earth Doped TiO2 and ZnWO4 with Different Morphologies,O643.36
  5. Study on Preparation of Novel Modified TiO2 Photocatalyst for Photodegradation of Organic Pollutants,O643.36
  6. The Synthesis of Structural Controllable Titanium Dioxide Nanorods Array and Its Electrochemical Performance,TB383.2
  7. Preparation of POM/TiO2 and Its Photocatalytic Degradation of Dye Wastewater,X791
  8. Preparation of Highly Reactive Anatase Titanium Dioxide and Its Application in Photocatalytic Hydrogen Generation,TQ116.2
  9. Synthesis and Photocatalystic Properties of the Visible-light-responding Photocatalysts Supported on LDHs,O643.3
  10. Study on the Preparation and Photocatalytic Activity of Titanium Dioxide Nanoparticles,O643.36
  11. First-principles Study on Magnetic and Optical Properties of Rutile TiO2,O614.411
  12. Study on the Synthesis of Tio2 /graphene Composite and Its High Photocatalytic Activity for Reducing Cr(VI),O643.36
  13. Preparation of Zeolite Doping Nano-TiO2 and Research of the Photocatalytic Properties,TB383.1
  14. A Study of Photocatalysis Degradation of Polybrominated Diphenyl Ethers (PBDEs),X70
  15. Scale Clean and Inhibition of Heat Exchanger in Sulfate Titanium Dioxide Process,TQ621.12
  16. Removal of Dye Elements from Colored Effluents by Porous Material,X791
  17. Typical odor substances in raw water Photocatalytic Degradation,O643.32
  18. Photocatalytic Degradation of Eosin Y in Water Using N,S-Doped TiO2 Catalyst,X703
  19. Study of Cadmium and Arsenate Co-adsorption on TiO2,X703
  20. TiO2/ACF Composite Photocatalytic Preparation and Its Photocatalytic Degradation Property,O643.36
  21. Preparation and Photocatalysis Property of TiO2/ACF Photocatalytic Material,O643.36

CLC: >
© 2012 www.DissertationTopic.Net  Mobile