http://www.cnr.it/ontology/cnr/individuo/prodotto/ID263904

Eu-doped alpha-Fe2O3 nanoparticles with modified magnetic properties. (Articolo in rivista)

Type

Label

Eu-doped alpha-Fe2O3 nanoparticles with modified magnetic properties. (Articolo in rivista) (literal)

Anno

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi

Alternative label

Freyria F. [1], Barrera G. [2], Tiberto P. [2], Belluso E. [3, 4], Levy D. [3], Saracco G. [1], Allia P. [1], Garrone E.[1], Bonelli B. [1] (2013)
Eu-doped alpha-Fe2O3 nanoparticles with modified magnetic properties.
in Journal of solid state chemistry (Online); Elsevier, Amsterdam (Paesi Bassi)
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

Freyria F. [1], Barrera G. [2], Tiberto P. [2], Belluso E. [3, 4], Levy D. [3], Saracco G. [1], Allia P. [1], Garrone E.[1], Bonelli B. [1] (literal)

Pagina inizio

Pagina fine

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#url

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

Rivista

Note

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

[1] Department of Applied Science and Technology and INSTM Unit, Politecnico Torino, Turin, Italy [2] Electromagnetism Department, INRIM, Turin, Italy [3] Earth Science Department, Università degli Studi di Torino, Turin, Italy [4] CNR - Istituto di Geoscienze Georisorse, Torino and NIS Excellence Centre, Unità di Torino, Università degli Studi di Torino, Turin, Italy (literal)

Titolo

Abstract

Eu-doping of hematite (?-Fe2O3) nanoparticles (NPs) takes place under hydrothermal conditions, and does not at ambient temperature and pressure. Required circumstances have been studied in detail. In the presence of Eu, besides hematite, some goethite and ferrihydrite are formed. Evidence for the occurrence of doping is reported. Chemical composition, as studied by EDS (bulk) and XPS (surface), reveals an enrichment of Eu at NPs core, ascribed to the occurrence of a two-step mechanism of NP formation, comprising nucleation at first, in which Eu3+ ions compete with Fe3+ ions, notwithstanding the large difference in concentration, and a successive growth step of NPs in a solution comparatively richer in Fe3+ species. The Eu content affects: (i) the morphology of NPs, as shown by TEM and FE-SEM; (ii) lattice parameters, as obtained by Rietveld refinement of XRD patterns; (iii) magnetic properties, due to the presence of Eu3+ ions, characterized by a higher one-ion anisotropy and a lower magnetic moment with respect to iron cations. (literal)

Editore