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Band Gap Implications on Nano-TiO? Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst.

ABSTRACT: The effect of surface modification using ascorbic acid as a surface modifier of nano-TiO? heterogeneous photocatalyst was studied. The preparation of supported photocatalyst was made by a specific paste containing ascorbic acid modified TiO? nanoparticles used to cover Polypropylene as a support material. The obtained heterogeneous photocatalyst was thoroughly characterized (scanning electron microscope (SEM), RAMAN, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and Diffuse Reflectance Spectra (DRS) and successfully applied in the visible light photodegradation of Alizarin Red S in water solutions. In particular, this new supported TiO? photocatalyst showed a change in the adsorption mechanism of dye with respect to that of only TiO? due to the surface properties. In addition, an improvement of photocatalytic performances in the visible light photodegration was obtained, showing a strict correlation between efficiency and energy band gap values, evidencing the favorable surface modification of TiO? nanoparticles.

SUBMITTER: D'Amato CA

PROVIDER: S-EPMC6116251 | biostudies-literature |

REPOSITORIES: biostudies-literature

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