In situ XANES studies of TiO 2/Fe 3O 4@C during photocatalytic degradation of trichloroethylene
Abstract
Mainly anatase and Fe 3O 4 in the magnetic photocatalysts (TiO 2 on Fe 3O 4@C core-shell nanoparticles (TiO 2/Fe 3O 4@C)) are observed by X-ray powder diffraction (XRD) spectroscopy. The Ti K-edge least-square fitted XANES spectra of the TiO 2/Fe 3O 4@C photocatalyst indicate that the main titanium species are nanosize TiO 2 (9 nm) (77%) and bulky TiO 2 (23%). Speciation of titanium in the TiO 2/Fe 3O 4@C during photocatalytic degradation of 100 ppm of trichloroethylene (TCE) has also been studied by in situ X-ray absorption near-edge structural (XANES) spectroscopy. TiO 2 is not perturbed during the course of photocatalysis. However, it is worth to note that during photocatalytic degradation of TCE, about 33% of FeO and 67% of Fe 3O 4 are observed in the photocatalyst. It seems that the carbon layer on the TiO 2/Fe 3O 4@C photocatalysts can reduce the possibility for photoexcited electron-hole recombination as usually found on the relatively narrow bandgap of ferric oxide during photocatalysis.
- Publication:
-
Nuclear Instruments and Methods in Physics Research A
- Pub Date:
- July 2010
- DOI:
- 10.1016/j.nima.2009.10.136
- Bibcode:
- 2010NIMPA.619...98H
