Unexpected Fe local order in iron oxide-coated nanocrystalline magnesium oxides with exceptional reactivities against environmental toxins

Citation
J. Moscovici et al., Unexpected Fe local order in iron oxide-coated nanocrystalline magnesium oxides with exceptional reactivities against environmental toxins, J SYNCHROTR, 8, 2001, pp. 925-927
Citations number
10
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF SYNCHROTRON RADIATION
ISSN journal
09090495 → ACNP
Volume
8
Year of publication
2001
Part
2
Pages
925 - 927
Database
ISI
SICI code
0909-0495(200103)8:<925:UFLOII>2.0.ZU;2-8
Abstract
Mg oxide nanoparticles are very reactive materials used to mitigate atmosph eric pollution and to sequester polluting molecules. Using Fe K-edge XAFS, we have studied the structure of iron oxide-coated MgO nanoparticles before and after reaction with CCl4. Before reaction, the local structure around Fe is totally different from that in iron oxide coatings on SrO and CaO nan oparticles, although these coated materials were prepared in the same way. In SrO and CaO, the iron oxide coating has been shown to be well separated from the bulk of the nanoparticle, whereas in MgO, Fe was found to mix with MgO. After reaction with CCl4, Fe-Cl bonds can be detected when the coated nanoparticle is saturated. Such Fe-Cl EXAFS signals have not been observed in previously studied nanoparticles.