Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Sol-gel formation of gamma-Fe2O3/SiO2 nanocomposites
Autore:
Solinas, S; Piccaluga, G; Morales, MP; Serna, CJ;
Indirizzi:
CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain CSIC Madrid Spain E-28049CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain Univ Cagliari, Dipartimento Sci Chim, Monserrato, Cagliari, Italy Univ Cagliari Monserrato Cagliari Italy him, Monserrato, Cagliari, Italy
Titolo Testata:
ACTA MATERIALIA
fascicolo: 14, volume: 49, anno: 2001,
pagine: 2805 - 2811
SICI:
1359-6454(20010816)49:14<2805:SFOGN>2.0.ZU;2-9
Fonte:
ISI
Lingua:
ENG
Soggetto:
IRON-OXIDE; SILICA MATRIX; NANOCRYSTALLINE GAMMA-FE2O3; MAGNETIC-PROPERTIES; X-RAY; NANOPARTICLES; DIFFRACTION; MOSSBAUER; CATALYSTS; FE2O3;
Keywords:
sol-gel; magnetic nanocomposite; phase transformation;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Engineering, Computing & Technology
Citazioni:
31
Recensione:
Indirizzi per estratti:
Indirizzo: Morales, MP CSIC, Inst Ciencia Mat, Plaza Murillo 2, E-28049 Madrid, SpainCSIC Plaza Murillo 2 Madrid Spain E-28049 28049 Madrid, Spain
Citazione:
S. Solinas et al., "Sol-gel formation of gamma-Fe2O3/SiO2 nanocomposites", ACT MATER, 49(14), 2001, pp. 2805-2811

Abstract

Fe2O3-SiO2 nanocomposites with Fe/Si molar concentrations ranging between 0.25 and 0.57 were prepared by the sol-gel route. Tetraethoxysilane and iron(III) nitrate solution in ethanol were mixed and the hydrolysis reaction was promoted by the hydration water of the salt. The sols were gelated in air and then treated at 400 degreesC for 4 h. The effect of the gelation process on the formation of the final nanocomposites has been investigated by studing different factors, such as temperature and surface of evaporation/volume ratio of the sot. Nanoparticles of gamma and/or alpha iron oxide phaseof different size were obtained in the silica matrix depending on the gelation conditions and on the later heat treatments. gamma -Fe2O3-SiO2 nanocomposites were obtained only when organic material was present into the poresof the gel silica matrix supporting their formation through a magnetite phase. At temperatures >400 degreesC, the y-phase begins to transform to the alpha -phase. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 11/07/20 alle ore 11:20:29