New generation photocatalysts: how tungsten influences the nanostructure and photocatalytic activity of TiO2 in the UV and visible regions.

Autor: Štengl V; Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i. , 250 68 Řež, Czech Republic. stengl@iic.cas.cz, Velická J, Maříková M, Grygar TM
Jazyk: angličtina
Zdroj: ACS applied materials & interfaces [ACS Appl Mater Interfaces] 2011 Oct; Vol. 3 (10), pp. 4014-23. Date of Electronic Publication: 2011 Oct 07.
DOI: 10.1021/am2008757
Abstrakt: Tungsten-doped anatase was prepared by a thermal hydrolysis of aqueous solutions of peroxo complexes of titanium and tungsten. The synthesized samples included X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction, Raman spectroscopy, specific surface area, and porosity determination. W doping resulted in a decrease of the unit-cell volume of anatase at lower W contents and an increase at higher W contents. The position of the most intense Raman band of the E(g) mode (near 147 cm(-1)) also has a local minimum at medium-doped titania (1.1-3.6% W in titania). W doping increases the temperature of anatase-to-rutile transformation by about 100 °C compared with nondoped anatase. The photocatalytic activity of doped titania samples was determined by decomposition of Orange II dye during irradiation at 365 and 400 nm. Specimens with moderate W doping (1.0-3.3% W) perform best: they enhance the corresponding reaction rates 10 times at 365 nm and 5 times at 400 nm, respectively, compared with pure titania obtained under the same set of synthesis conditions.
(© 2011 American Chemical Society)
Databáze: MEDLINE