Synthesis and characterization of iron - cobalt nanoparticles embedded in mesoporous silica MCM - 41

• Autorzy: Surowiec Z. , Wiertel M. , Budzyński M. , Gac W.
• Konferencja: Proceedings of the 9th All - Polish Seminar on Mössbauer Spectroscopy OSSM'2012, 10-13 June 2012, Lublin - Kazimierz Dolny, Poland
• Języki publikacji: EN

Abstrakty

EN

Fe1.xCox/MCM-41 nanocomposite materials were prepared by wet impregnation of the silica mesoporous support with aqueous solution of iron and cobalt salt mixtures. Samples, after calcination, were reduced at 573 K in order to obtain homogeneous distribution of (Fe-Co)3O4 oxide species over the MCM-41 support. Bimetallic systems were achieved through high temperature reduction, carried out at 1073 K. The temperature-programmed reduction studies indicated complex nature of the oxide species. The phase analysis of the obtained samples after low temperature reduction process carried out by means of X-ray diffraction method and using 57Fe Mossbauer spectroscopy revealed the presence of nanostructured magnetite- and maghemite-like phases. The samples with higher cobalt contents (x . 0.2) contained additionally bimetallic phases. The complete transformation of oxide phases to bimetallic Fe-Co systems occurred during reduction process in hydrogen at 1073 K. It was observed that high temperature processing caused partial transformation of highly dispersed iron oxide nanocrystallites into fayalite species embedded in the silica walls.

Słowa kluczowe

EN

cobalt; iron; MCM-41 porous silica; Mössbauer effect; superparamagnetic nanoparticles

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2013
• Tom: Vol. 58, No. 1
• Strony: 87--92
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Surowiec Z.

autor

Wiertel M.

autor

Budzyński M.

autor

Gac W.

• Maria Curie-Skłodowska University, Institute of Physics, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: [phone], Fax: [phone],

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