engleski

Titania Based Nanostructures for various applications

Titania based nanostructures have been extensively investigated materials because of their promising physical and chemical properties, such as a high specific surface area, the low costs of synthesis, a high photo-activity and environmental stability. Titanate (H2Ti3O7) nanotubes (TiNT) exhibit some distinct advantages as high density of surface OH- groups that enable surface modifications, and ion- exchange. Different surface modification of TiNT and TiO2 nanotubes (TiO2NT) array with the aim to manipulate with the nanotubes properties toward various applications will be presented. TiNTs were synthesized by hydrothermal method, while TiO2NT arrays were prepared by anodization of titanium plates. In case of nanotubes decorated by the silver particles the photo-reduction of AgNO3 under UV light were used. Pure and Ag- decorated nanotubes were further modified by heat treatment in hidrogen. TiNT were surface-modified with (3-aminopropyl)trimethoxy silane (APTMS) and imbuilt in the epoxy matrix as nanofiller. For preparation of BaTiO3/TiO2 nanotubes heterostructure (BTO/TiO2NT), TiO2NT arrays were hydrothermally treated. The structural characterization was done using TEM, XRD and Raman spectroscopy. The band gaps and the photo- catalytic activity were studied using UV–ViS-NIR spectroscopy. Polymer nanocomposites were studied by dynamic mechanical analysis, while the persistent photoconductivity in BTO/TiO2NT was studied by impedance spectroscopy. We found that high temperature hydrogenation of pure and Ag decorated nanotubes is essential to increase the absorption of light in the visible and near-IR regions. Both hydrogenated and Ag decorated sample had higher photo-degradation impact on model organic compounds (wastewater) as a consequence of the increased absorption of visible light and the synergetic effects of the surface plasmon resonance of Ag nanoparticles and oxygen vacancies.

Titania; nanostructures; nanocomposites

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