Search results for "Photocatalysis."
showing 10 items of 584 documents
Photocatalytic Selective Oxidation of 5-(Hydroxymethyl)-2-furaldehyde to 2,5-Furandicarbaldehyde in Water by Using Anatase, Rutile, and Brookite TiO2…
2013
5-(Hydroxymethyl)-2-furaldehyde (HMF) was selectively oxidized to 2,5-furandicarbaldehyde (FDC) in; aqueous medium by using home prepared (HP) anatase, rutile, and brookite TiO2 nanoparticles. HP samples were prepared via a sol-gel method by using TiCl4 as the TiO2 precursor. Commercial TiO2 catalysts were also used for, comparison. All samples were characterized by BET specific surface area, XRD, TGA, and SEM, and the reactivity results showed that HP catalysts are predominantly amorphous and give rise to selectivities toward FDC more than twice that of commercial and well crystallized catalysts.
Black carbon-doped TiO2 films: Synthesis, characterization and photocatalysis
2019
This research is funded by the European Social Fund according to the activity ‘Improvement of researchers’ qualification by implementing world-class R&D projects’ of Measure No. 09.3.3-LMT- K-712, project „Investigation of the application of TiO2 and ZnO for the visible light assisted photocatalytical disinfection of the biologically contaminated water“ (09.3.3-LMT-K-712-01-0175). The authors express gratitude for the S. Tuckute, M. Urbonavicius, G. Laukaitis and K. Bockute for their valuable input in current work. © 2019. This work is licensed under a CC BY-NC-ND 4.0 license.
Home-prepared anatase, rutile, and brookite TiO2 for selective photocatalytic oxidation of 4-methoxybenzyl alcohol in water: reactivity and ATR-FTIR …
2009
5th European Meeting on Solar Chemistry and Photocatalysis -- OCT 04-08, 2008 -- Palermo, ITALY
Photocatalytic thin films of TiO2 formed by a sol-gel process using titanium tetraisopropoxide as the precursor
2008
Abstract Thin TiO 2 films were prepared with the dip-coating technique by using sols deriving from titanium tetraisopropoxide. TiO 2 films were formed on glass substrates previously covered by a SiO 2 layer obtained from a tetraethylortosilicate sol. The films, after a thermal treatment at 673 K, mainly consisted of TiO 2 anatase. The samples were characterised by X-ray diffraction, UV–Vis spectroscopy, scanning electron microscopy and atomic force microscopy. The photoactivity of the various films was tested by using as probe reaction the photo-oxidation of 2-propanol in gas-solid regime. The photoreactivity results indicated that the TiO 2 films were efficient for degrading 2-propanol und…
Original Approach to Synthesize TiO2/ZnO Hybrid Nanosponges Used as Photoanodes for Photoelectrochemical Applications
2021
[EN] In the present work, TiO2/ZnO hybrid nanosponges have been synthesized for the first time. First, TiO2 nanosponges were obtained by anodization under hydrodynamic conditions in a glycerol/water/NH4F electrolyte. Next, in order to achieve the anatase phase of TiO2 and improve its photocatalytic behaviour, the samples were annealed at 450 degrees C for 1 h. Once the TiO2 nanosponges were synthesized, TiO2/ZnO hybrid nanosponges were obtained by electrodeposition of ZnO on TiO2 nanosponges using different temperatures, times, and concentrations of zinc nitrate (Zn(NO3)(2)). TiO2/ZnO hybrid nanosponges were used as photoanodes in photoelectrochemical water splitting tests. The results indi…
Study of phase composition, photocatalytic activity, and photoluminescence of TiO2 with Eu additive produced by the extraction-pyrolytic method
2021
The Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. The work was also partially supported by the LZP grant 2020/2-0074. R. Burve has been supported by the project “Synthesis of nanostructured materials based on titanium dioxide and tin dioxide and investigation of their physicochemical properties” Nr. MP-2019/7, for strengthening scientific personnel capacity 2019/2020 at the Riga Technical University. Authors are grateful to Dr. K. Šmits for the microscopic measurements and SEM images.
Photocatalytic oxidation of gaseous toluene on anatase TiO2 catalyst: Mechanistic aspects and FT-IR investigation
1999
Abstract Photo-oxidation of toluene has been carried out in gas–solid regime by using polycrystalline anatase TiO2 as the catalyst. The reacting gaseous mixture was toluene, air and water in various molar ratios. A pyrex fixed-bed continuous photoreactor irradiated by a medium pressure Hg lamp was used for performing the photoreactivity experiments. The main oxidation product was benzaldehyde but benzene, benzyl alcohol and traces of benzoic acid, phenol and unidentified compounds were also detected. The molar conversion to benzaldehyde with respect to the initial amount of toluene was ca. 20% in the best experimental conditions. Benzene was produced only as a transient product during the f…
Photocatalytic activity of anatase-nickel ferrite heterostructures
2015
The simple co-precipitation route was used to couple commercial TiO2 anatase nanopowder with nickel ferrite (NiFe2O4). The morphology and the crystalline structure of composite nanoparticles were characterised by TEM, N2 adsorption-desorption, XRD and Rietveld refinement, XPS and XAS. The optical and magnetic properties were investigated. After co-precipitation NiFe2O4 nanoparticles, composed of spinel ferrite crystal phase, were formed on the surface of TiO2 anatase nanopowder. The TiO2/NiFe2O4 composite oxide demonstrated large specific surface area, high visible light absorption efficiency and efficient charge carrier separation, compared to pristine anatase TiO2 or pristine NiFe2O4, rep…
Physicochemical characterization of metal hexacyanometallate–TiO2composite materials
2015
The paper describes the synthesis and characterization of novel TiO2–metal hexacyanometallates (MHCMs) composite materials. The starting material, TiO2, was modified by addition of cobalt-hexacyanoferrate (CoHCF) or iron-hexacyanocobaltate (FeHCC) at various concentrations. The resulting composites were characterized as follows: cyclic voltammetry (CV) followed the formation of TiO2–MHCM clusters, TEM micrographs studied their morphology, XAS and XPS data indicated that MHCM bonds to TiO2 through the nitrogen atom of its –CN group and modifies the environment of Ti compared to that of pure anatase. As expected, and confirmed by UV-Vis and XP-valence band data, the electronic properties of T…
Surface properties of iron-titania photocatalysts employed for 4-nitrophenol photodegradation in aqueous TiO2 dispersion
1994
Iron(III) doped specimens (0.01–5% atomic Fe ∶ Ti) have been prepared by impregnating polycrystalline “home prepared” TiO2 (mainly anatase) and have been studied for photocatalytic degradation of 4-nitrophenol in aqueous dispersions. Some structural and surface properties have been studied by X-ray diffraction, specific surface area and porosity measurements and FTIR monitoring of pyridine, ammonia and methanoic acid adsorption for surface acidity and basicity. Their surface properties were compared with a corresponding series of photocatalysts prepared by a coprecipitation method. Adsorption of pyridine and ammonia indicates the presence of surface acid Lewis sites, a low concentration of …