The magnetic transition in ε-Fe.sub.2./sub.O.sub.3./sub. nanoparticles: magnetic properties and hyperfine interactions from Mössbauer spectroscopy

0454302 - FZÚ 2016 RIV US eng J - Journal Article
Kohout, J. - Brázda, Petr - Závěta, K. - Kubániová, D. - Kmječ, T. - Kubíčková, L. - Klementová, Mariana - Šantavá, Eva - Lančok, Adriana
The magnetic transition in ε-Fe₂O₃ nanoparticles: magnetic properties and hyperfine interactions from Mössbauer spectroscopy.
Journal of Applied Physics. Roč. 117, č. 17 (2015), "17D505-1"-"17D505-4". ISSN 0021-8979. E-ISSN 1089-7550
R&D Projects: GA ČR GAP204/10/0035
Institutional support: RVO:68378271 ; RVO:61388980
Keywords : ε-Fe₂O₃ * magnetic transition * Mössbauer spectroscopy * X-ray powder diffraction
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.101, year: 2015

The nanoparticles of e-Fe2O3 enriched with 57Fe isotope in amorphous silica matrix were prepared by sol-gel technique starting from a single molecular precursor for both Fe2O3 and silica. From the X-ray powder diffraction pattern e-Fe2O3 was identified as the major phase and a-Fe2O3 and b-Fe2O3 were observed as minor iron oxide phases. Using the log-normal distribution for fitting the experimental data from the TEM micrographs, the characteristic size of particles d0 similar to 25 nm was derived. The rather high coercivity of similar to 2.1 T at room temperature was confirmed for our nanoparticle system. From the de pendences of magnetization on temperature a two-step magnetic transition spread between 100 K and 153 K was indicated.
Permanent Link: http://hdl.handle.net/11104/0255015