Various Preparation Of TiO₂Based Nanocomposite Materials And Photocatalytic Performance

The TiO2based composite materials in this study were prepared by microwaveirradiation, building three-dimensional ordered macroporous morphology and self-assemblyto obtain a series of nanocomposites: Ag/TiO2-MW(t),3DOM Ag/TiO2and3DOMPW11Co-APS-TiO2. The phase composition, structures and morphologies werewell-characterized via FT-IR spectrometer (FT-IR), X-ray diffraction (XRD), Inductivelycoupled pasma atomic emission spectrometry (ICP-AES), UV-Vis diffuse reflectance spectra(UV-Vis/DRS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM)and N2adsorption-desorption tests. The results of Ag/TiO2-MW(t) showed that thecrystallineand morphology was changed for the better. The phase of Ag/TiO2which wasprepared under microwave irradiation5min was the best, whose surface area was100.64m2·g-1. The silver species in the nanocomposite Ag/TiO2by microwave irradiation wasmetallic Ag0. Compared with the composite without microwave irradiation, of which wassmall size, good structure and orderly distribution of particles. The results of3DOM Ag/TiO2showed that3DOM Ag/TiO2had anatase crystalline structure and Ag in the3DOM Ag/TiO2was metallic Ag0. The3DOM Ag/TiO2was highly ordered structure and the mesoporous wallof3DOM Ag/TiO2was made by P123. Compare with Degussa P-25, it was clearly observedthat the absorption band was red-shifed to the visible region. The results of3DOMPW11Co-APS-TiO2showed that the primary Keggin structures remained intact in as-preparedcomposites, of the same time,3DOM TiO2had anatase crystalline structure, and PW11Co wassuccessfully bonded to3DOM TiO2by Co-N bond. Compared with3DOM TiO2and PW11Co,it was observed that the absorption band was clearly broaden, and the three-dimensionalordered macroporous structure of product basically remained, the opening and permeabilitymacroporous could significantly improve the accessibility of diffusing species.To investigate the photocatalytic activities of the TiO2based composite materials, someexperiments were studied. Firstly, the photocatalytic activities of Ag/TiO2-MW(t) and3DOMAg/TiO2were studied by the UV irradiation photodegradation of methyl orange as a modelmolecule. At the same time, we choose different types of organic pollutants as reactants toevaluate the photocatalytic activities of Ag/TiO2-MW(t) and3DOM Ag/TiO2under UVirradiation. Secondly, the photocatalytic activity of3DOM PW11Co-APS-TiO2was studied with Rhodamine B as the model molecule under UV irradiation. The photocatalyticdegradation of organic pollutants with different modes was reserched to investigate thephotocatalytic activity of3DOM PW11Co-APS-TiO2. The results showed that under the sameexperimental conditions, the synthesized composite exhibited high photocatalytic activitywhich was significantly higher than that of the comparative system and other monomers. Thesynthesized samples all exhibited high photocatalytic activities for the organic pollutants withdifferent structures and its photocatalytic ability was also widely applied on the degradationof dye.