(FexCo1-x)y(SiO2)1-y nanocomposites were prepared by a sol-gel method, using tetraethoxysilane and metal acetates as precursors. Two sets of xerogel samples were prepared: in the first set x was kept equal to 0.5 and four y values were selected in the range 0.02-0.2; in the second set y was kept equal to 0.1 and three samples with x equal to 0.45, 0.50, and 0.70 were prepared. The samples were characterized by X-ray diffraction, TEM, and HREM to verify the formation of the FeCo alloy nanocrystals and to investigate their structure, morphology, and composition. All samples contain spherical FeCo alloy nanoparticles uniformly dispersed in the silica matrix with average size increasing with metal content. Magnetic measurements carried out on selected samples show a superparamagnetic behavior, with blocking temperature which depends on metal load, as a consequence of particle distance variation.

Influence of metal content on size, dispersion, and magnetic properties of iron-cobalt alloy nanoparticles embedded in silica matrix / G. Ennas, A. Falqui, S. Marras, C. Sangregorio, G. Marongiu. - In: CHEMISTRY OF MATERIALS. - ISSN 0897-4756. - 16:26(2004), pp. 5659-5663. [10.1021/cm048761e]

Influence of metal content on size, dispersion, and magnetic properties of iron-cobalt alloy nanoparticles embedded in silica matrix

A. Falqui
Secondo
;
2004

Abstract

(FexCo1-x)y(SiO2)1-y nanocomposites were prepared by a sol-gel method, using tetraethoxysilane and metal acetates as precursors. Two sets of xerogel samples were prepared: in the first set x was kept equal to 0.5 and four y values were selected in the range 0.02-0.2; in the second set y was kept equal to 0.1 and three samples with x equal to 0.45, 0.50, and 0.70 were prepared. The samples were characterized by X-ray diffraction, TEM, and HREM to verify the formation of the FeCo alloy nanocrystals and to investigate their structure, morphology, and composition. All samples contain spherical FeCo alloy nanoparticles uniformly dispersed in the silica matrix with average size increasing with metal content. Magnetic measurements carried out on selected samples show a superparamagnetic behavior, with blocking temperature which depends on metal load, as a consequence of particle distance variation.
Sol-gel method; nanocomposites; spectroscopy; nanocrystals
Settore FIS/03 - Fisica della Materia
2004
Article (author)
File in questo prodotto:
File Dimensione Formato  
Influence of metal content on size, dispersion, and magnetic properties of iron− cobalt alloy nanoparticles embedded in silica matrix CHEM MATER.pdf

accesso riservato

Descrizione: Articolo principale
Tipologia: Publisher's version/PDF
Dimensione 372.44 kB
Formato Adobe PDF
372.44 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/780350
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 51
  • ???jsp.display-item.citation.isi??? 52
social impact