FORMATION CONDITIONS OF A MAGNETICALLY ORDERED PHASE ε-Fe2O3: A FMR IN SITU STUDY
S. S. Yakushkin, G. A. Bukhtiyarova, O. N. Martyanov
G. K. Boreskov Institute of Catalysis, Siberian Division, Russian Academy of Sciences, Novosibirsk
Keywords: ferromagnetic resonance, supermagnetic nanoparticles, heterogeneous catalysts, in situ
Abstract
The ferromagnetic resonance (FMR) method in situ is used to study the initial stages of the formation of ε iron oxide nanoparticles deposited on silica gel at temperatures up to 600°C. It is shown that at high-temperature treatment of starting samples obtained by impregnation with an iron(II) sulfate solution, supermagnetic ε-Fe2O3/SiO2 nanoparticles form with a narrow size distribution. An analysis of the FMR data in comparison with the data of other methods enables the formulation of the formation conditions for systems of deposited ε-Fe2O3 nanoparticles without other polymorph impurities.
|
