Original scientific paper

Synthesis, Structural Characterization and Magnetic Properties of Iron Boride Nanoparticles with or without Silicon Dioxide Coating

Mislav Mustapić ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Damir Pajić ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Nikolina Novosel ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Emil Babić ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Krešo Zadro ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Marina Cindrić ; Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
Joseph Horvat ; Institute for Superconducting and Electronic Materials, University of Wollongong, Northfields Avenue, NSW 2522 Wollongong, Australia
Željko Skoko ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Mirjana Bijelić ; Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Andrey Shcherbakov ; Institute for Superconducting and Electronic Materials, University of Wollongong, Northfields Avenue, NSW 2522 Wollongong, Australia

Abstract

Nanoparticles of iron boride (Fe2B, Fe2B coated in SiO2, FexCo2−xB coated in SiO2) were synthesized
using the reduction of metal ions by sodium borohydride. X-ray diffraction confirms the amorphicity
of the coated compounds and scanning electron microscope imaging revealed the nanoparticulated structure
of all compounds. The splitting between zero-field-cooled and field-cooled temperature dependent
magnetization curves point to the blocking of superparamagnetic particles magnetization. Magnetic hysteresis
loops are however consistent with the combined effects of blocked superparamagnetic and ferromagnetic
(multidomain) particles. The observed quite complex magnetic behaviour is in accordance with
structural studies, where additional phases and broad distribution of particle sizes were identified.

Keywords

Fe-B; Fe-Co-B; SiO2 coating; magnetic nanoparticles; amorphous alloy

Hrčak ID:

62204

URI

https://hrcak.srce.hr/62204

Publication date:

5.10.2010.

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