| People | Locations | Statistics |
|---|---|---|
| Naji, M. |
| |
| Motta, Antonella |
| |
| Aletan, Dirar |
| |
| Mohamed, Tarek |
| |
| Ertürk, Emre |
| |
| Taccardi, Nicola |
| |
| Kononenko, Denys |
| |
| Petrov, R. H. | Madrid |
|
| Alshaaer, Mazen | Brussels |
|
| Bih, L. |
| |
| Casati, R. |
| |
| Muller, Hermance |
| |
| Kočí, Jan | Prague |
|
| Šuljagić, Marija |
| |
| Kalteremidou, Kalliopi-Artemi | Brussels |
|
| Azam, Siraj |
| |
| Ospanova, Alyiya |
| |
| Blanpain, Bart |
| |
| Ali, M. A. |
| |
| Popa, V. |
| |
| Rančić, M. |
| |
| Ollier, Nadège |
| |
| Azevedo, Nuno Monteiro |
| |
| Landes, Michael |
| |
| Rignanese, Gian-Marco |
|
Hanson, Jonathan
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (1/1 displayed)
Places of action
| Organizations | Location | People |
|---|
article
Physical and Chemical Properties of Ce₁-xZrxO₂ Nanoparticles and Ce₁-xZrxO₂ (111) Surfaces: Synchrotron-based Studies
Abstract
In this article, we review a series of studies that use synchrotron-based techniques (high-resolution photoemission, time-resolved x-ray diffraction, and x-ray absorption near-edge spectroscopy) to investigate the physical and chemical properties of Ce?-xZrxO? nanoparticles and Ce?-xZrxO? (111) surfaces (x ? 0.5). Ce O? and Ce?-xZrxO? particles in sizes between 3 and 7 nm were synthesized using a novel microemulsion method. The results of XANES (O K-edge, Ce and Zr LIII-edges) indicate that the Ce?-xZrxO? nanoparticles and Ce?-xZrxO? (111) surfaces have very similar electronic properties. For these systems, the lattice constant decreased with increasing Zr content, varying from 5.40 ? in CeO? to 5.27 ? in Ce???Zr???O?. Within the fluorite structure, the Zr atoms exhibited structural perturbations that led to different types of Zr-O distances and non-equivalent O atoms in the Ce?-xZrxO? compounds. The Ce?-xZrxO? nanoparticles were more reactive towards H? and SO? than the Ce?-xZrxO? (111) surfaces. The Ce?-xZrxO? (111) surfaces did not reduce in hydrogen at 300 C. At temperatures above 250 C, the Ce?-xZrxO? nanoparticles reacted with H? and water evolved into gas phase. XANES showed the generation of Ce??cations without reduction of Zr??. There was an expansion in the unit cell of the reduced nanoparticles probably as a consequence of a partial Ce??? Ce?? transformation and the sorption of hydrogen into the bulk of the material. S K-edge XANES spectra pointed to SO? as the main product of the adsorption of SO? on the Ce?-xZrxO? nanoparticles and Ce?-xZrxO? (111) surfaces. Full dissociation of SO? was seen on the nanoparticles but not on the Ce?-xZrxO? (111) surfaces. The metal cations at corner and edge sites of the Ce?-xZrxO? nanoparticles probably play a very important role in interactions with the H? and SO? molecules.