Preparation of core–shell nanostructured black nano-TiO2 by sol–gel method combined with Mg reduction
28 Dec 2018-Journal of Materials Research (Springer International Publishing)-Vol. 33, Iss: 24, pp 4173-4181
TL;DR: In this paper, black nano-TiO2 samples with core-shell nanostructure were successfully prepared by sol-gel method combined with Mg reduction using butyl titanate as titanium source and calcining at 500°C in air atmosphere and at 400-600°c in nitrogen atmosphere.
Abstract: Black nano-TiO2 samples with core–shell nanostructure were successfully prepared by sol–gel method combined with Mg reduction using butyl titanate as titanium source and calcining at 500°C in air atmosphere and at 400–600°C in nitrogen atmosphere. The prepared black TiO2 samples were characterized by X-ray diffraction, high resolution transmission electron microscopy, Raman spectra, photoluminescence emission spectra, N2 adsorption–desorption, and ultraviolet–visible spectroscopy. The results show that the black TiO2 exhibits a crystalline core–disordered shell structure composed of disordered surface and oxygen vacancies, and the thickness of the disordered layer is about 2–3 nm. The optical absorption properties of black nano-TiO2 samples have been remarkably enhanced in visible light region. Compared with the white TiO2, the reduced black TiO2 samples exhibit enhanced photocatalytic hydrogen production under the full solar wavelength range of light, and the sample prepared with the Mg and TiO2 ratio of 9:1 calcined at 500 °C has the maximum hydrogen production rate.
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TL;DR: In this paper, the authors summarized the significant properties of black TiO2 and identified some of the conflicting points observed in literature where further light needs to be shed for better understanding, including role of defects in overall photoactivity, photoactivity under visible spectrum, existence/coexistence of Ti3+ species and oxygen vacancies and their location, connection between band gap values and photocatalytic activity etc.
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TL;DR: It is shown that disorder-engineered TiO2 nanocrystals exhibit substantial solar-driven photocatalytic activities, including the photo-oxidation of organic molecules in water and the production of hydrogen with the use of a sacrificial reagent.
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TL;DR: The recent progress in the investigation of black TiO2 nanomaterials has been reviewed here, and special emphasis has been given on their fabrication methods along with their various chemical/physical properties and applications.
Abstract: In the past few decades, there has been a wide research interest in titanium dioxide (TiO2) nanomaterials due to their applications in photocatalytic hydrogen generation and environmental pollution removal. Improving the optical absorption properties of TiO2 nanomaterials has been successfully demonstrated to enhance their photocatalytic activities, especially in the report of black TiO2 nanoparticles. The recent progress in the investigation of black TiO2 nanomaterials has been reviewed here, and special emphasis has been given on their fabrication methods along with their various chemical/physical properties and applications.
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