English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/118089
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:

Title

Fe K-edge X-ray absorption spectroscopy study of nanosized nominal magnetite

AuthorsPiquer, Cristina; Laguna-Marco, M. A.; Roca, Alejandro G. ; Boada, R.; Guglieri, C.; Chaboy, Jesús
Issue Date2014
PublisherAmerican Chemical Society
CitationJournal of Physical Chemistry C 118(2): 1332-1346 (2014)
AbstractWhen studying nominal magnetite nanoparticles, it is mandatory to obtain a precise structural characterization to get an accurate relationship with their physiochemical properties. The great deal of information accumulated to date on the characterization of nominal magnetite and maghemite NPs does not clarify if the synthesized materials are single o multiphase systems involving bulk-like stoichiometric oxides (Fe3O4, γ-Fe2O 3, α-Fe2O3,...), or single or multiphase entities formed by nonstoichiometric oxides. In this work we propose a new approach to determine the structure of Fe oxide NPs by using the Fe K-edge X-ray absorption near edge spectroscopy. We report here an X-ray absorption near edge spectroscopy study at the Fe K-and L2,3-edges, on nominal magnetite nanoparticles synthesized by different methods. In addition, X-ray magnetic circular dichroism was recorded at the Fe L2,3-edges, in selected samples. We have found that the experimental spectra are not well reproduced by any linear combination of the absorption spectra of Fe3O4 and γ-Fe2O3 bulk references, even taking into account other oxides as goethite or ferrihydrite. The analysis of the Fe K-edge XANES spectra shows that it is the size, and not the synthesis method, which determines the structure of the NPs. Our experimental results indicate that, irrespective of the synthesis method, the nominal magnetite NPs are, actually, a single phase non stoichiometric Fe3-δO4 oxide. At the origin of this phase are the cation vacancies, which lead to the modification of the structural arrangements at the Fe sites with respect to those found in bulk-like iron oxides. © 2013 American Chemical Society.
URIhttp://hdl.handle.net/10261/118089
DOI10.1021/jp4104992
Identifiersdoi: 10.1021/jp4104992
issn: 1932-7447
e-issn: 1932-7455
Appears in Collections:(ICMA) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.