Search results for "TiO2"

Cu-dopēto titāna dioksīda DFT modelēšana antibakteriālo īpašību izpētei

2022

Titāna dioksīda (TiO2) visu trīs polimorfu (anatass, rutils, brokīts) nanodaļiņām piemīt antibakteriālās īpašības, tomēr vislabāk tās ir izteiktas anatasam. TiO2 antibakteriālās īpašības var skaidrot ar tā dabu - tas ir pusvadītājs - fotokatalizators. Lai uzlabotu fotokatalītiskās īpašības, TiO2 iespējams dopēt. Šajā darbā tiek aplūkotas divu TiO2 polimorfu - anatasa un rutila - dopēšana ar vara (Cu) atomiem, kas, balstoties uz eksperimentāliem datiem, var sekmēt antibakteriālo īpašību uzlabošanos. Tika uzbūvēti anatasa un rutila tilpuma un virsmas modeļi bez un ar Cu atomu, no pirmajiem principiem tiek aprēķināta tīra un ar Cu dopēto TiO2 divu polimorfu (anatasa, rutila) tilpuma fāze, tiek…

Brookite, the least known TiO2 photocatalyst, Catalysts

2013

Brookite is the least studied TiO2 photocatalyst due to the difficulties usually encountered in order to obtain it as a pure phase. In this review, a comprehensive survey of the different methods available for preparing brookite powders and films is reported. Attention has been paid both to the most traditional methods, such as hydrothermal processes at high temperatures and pressures, and to environmentally benign syntheses using water soluble compounds and water as the solvent. Papers reporting the photocatalytic activity of pure and brookite-based samples have been reviewed.

Studio dell’Influenza del Carbonio Attivo sulla Degradazione Fotocatalitica del 2-Propanolo Condotta in Presenza di Biossido di Titanio o di Ossido d…

2010

Extruded Expanded Polystyrene Sheets Coated by TiO2 as New Photocatalitic Materials for Foodstuffs Packaging

2012

Nanostructured, photoactive anatase TiO2 sol prepared under very mild conditions using titanium tetraisopropoxide as the precursor is used to functionalise extruded expanded polystyrene (XPS) sheets by spray-coating resulting in stable and active materials functionalised by TiO2 nanoparticles. Photocatalytic tests of these sheets performed in a batch reactor in gas-solid system under UV irradiation show their successful activity in degrading probe molecules (2-propanol, trimethylamine and ethene). Raman spectra ensure the deposition of TiO2 as crystalline anatase phase on the polymer surface. The presence of TiO2 with respect to polymer surface can be observed in SEM images coupled to EDAX …

Environmentally Friendly Photocatalytic Oxidation of Aromatic Alcohol to Aldehyde in Aqueous Suspension of Brookite TiO(2)

2008

WOS: 000260509000008

Reactive Polymers: A Versatile Toolbox for the Immobilization of Functional Molecules on TiO2 Nanoparticles

2006

Photoelectrocatalytic selective oxidation of 4-methoxybenzyl alcohol in water by TiO2 supported on titanium anodes

2013

The photoelectrocatalytic partial oxidation of 4-methoxybenzyl alcohol in aqueous solution irradiated by near-UV light was carried out in a three-electrode batch reactor. TiO2 films were either deposited by dip-coating of a TiO2 sol onto a Ti foil and subsequent calcination or generated on Ti plates by thermal oxidation in air at 400-700 degrees C. The effects of the anode preparation method and bias potential values on conversion and selectivity to the corresponding aldehyde were investigated. The photoelectrocatalytic results were compared with the photocatalytic and electrocatalytic ones. The results indicated that no reaction occurred during the electrocatalytic experiments, whereas the…

Overview on oxidation mechanisms of organic compounds by TiO2 in heterogeneous photocatalysis

2012

This review provides the reader with a general overview on heterogeneous photocatalytic oxidation mechanisms in the presence of TiO2, with a special address to conversion of aliphatic and aromatic organic species. The aim was to clarify the steps of the photo-oxidation of the various classes of compounds and to relate them with the properties of the catalysts and the experimental conditions used. Reactions carried out to perform complete degradation and photocatalytic partial oxidations have been deeply discussed. Recent isotopic studies highlighted new reaction pathways concerning partial oxidation of alcohols to aldehyde and oxidation of benzene while EPR investigations confirmed that not…

Aqueous selective photocatalytic oxidation of salicyl alcohol by TiO2 catalysts: Influence of some physico-chemical features

2021

Abstract Partial photocatalytic oxidation of salicyl alcohol (2-hydroxybenzyl alcohol) to salicylaldehyde in water was investigated under environmental friendly conditions in the presence of home-prepared and commercial TiO2 (Merck and Aeroxide P25) samples under UVA irradiation. The photocatalysts were characterized by using BET, XRD, SEM and/or TEM techniques. The effects of crystallinity degree, pH (3–11) and presence of a hole trap (ethanol) on the photocatalytic activity and product selectivity were investigated. 4-Hydroxybenzyl alcohol was also used to study the influence of the position of the substituent group in the aromatic ring. High alcohols conversion and product selectivity va…

Nanostructured rutile TiO2 for selective photocatalytic oxidation of aromatic alcohols to aldehydes in water

2008

WOS: 000253100100022