title: Preparation of silver-modified TiO2 via microwave-assisted method and its photocatalytic activity for toluene degradation.
abstract: Silver-modified TiO(2) (Ag-TiO(2)) with various Ag/Ti molar ratios were prepared by the microwave-assisted method and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and UV-vis diffuse reflectance spectroscopy (UV-vis-DRS). Compared with the hydrothermal method, Ag-TiO(2) of small crystallite size and high crystallinity can be obtained by the microwave-assisted preparation method. When the Ag/Ti molar ratio increased from 0 to 2%, the doping of Ag promoted the phase transformation and inhibited the growth of anatase crystallite. The absorption edge of Ag-TiO(2) shifted to longer wavelength, and the band gap energy of Ag-TiO(2) decreased. However, after increasing the molar ratio Ag/Ti further from 2 to 4%, the anatase content, the crystallite size and the band gap energy of Ag-TiO(2) only increased slightly. In photodegradation gaseous toluene, the photocatalytic activity of Ag-TiO(2) increased with the increase of Ag/Ti molar ratio from 0 to 1%, but declined with the further increase to 2%. The optimal Ag/Ti molar ratio for photocatalytic activity of Ag-TiO(2) was found as 1%, with the content of anatase, rutile and brookite of 71.1, 14.5 and 14.4%, respectively. Compared with TiO(2), Ag-TiO(2) exhibited a better photostability in toluene degradation.
authors.affiliation: Environmental Science Research Institution, Huazhong University of Science and Technology, No 1037 Luoyu Road, Wuhan 430074, PR China.
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Li
authors.forename: Linling
authors.initials: L
authors.lastname: Wang
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Lu
mesh_terms: D002384:Catalysis; D052918:Environmental Restoration and Remediation / Q000379:methods; D015386:Hazardous Substances; D007220:Industrial Waste / Q000517:prevention & control; D008722:Methods; D008872:Microwaves; D055668:Photochemical Processes; D012834:Silver / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014050:Toluene / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D015386:Hazardous Substances; D007220:Industrial Waste; C009495:titanium dioxide; D014050:Toluene; D012834:Silver; D014025:Titanium