Mössbauer Studies of Core-Shell FeO/Fe{sub 3}O{sub 4} Nanoparticles
- Kazan Federal University (Russian Federation)
- University of South Florida, Department of Physics (United States)
FeO/Fe{sub 3}O{sub 4} nanoparticles were synthesized by thermal decomposition. Electron microscopy revealed that these nanoparticles were of the core-shell type and had a spherical shape with an average size of ~20 nm. It was found that the obtained FeO/Fe{sub 3}O{sub 4} nanoparticles had exchange coupling. The effect of anisotropy on the efficiency of heating (hyperthermic effect) of FeO/Fe{sub 3}O{sub 4} nanoparticles by an external alternating magnetic field was examined. The specific absorption rate (SAR) of the studied nanoparticles was 135 W/g in the experiment with an external alternating magnetic field with a strength of 600 Oe and a frequency of 310 kHz. These data led to an important insight: the saturation magnetization is not the only factor governing the SAR, and the efficiency of heating of magnetic FeO/Fe{sub 3}O{sub 4} nanoparticles may be increased by enhancing the effective anisotropy. Mössbauer spectroscopy of the phase composition of the synthesized nanoparticles clearly revealed the simultaneous presence of three phases: magnetite Fe{sub 3}O{sub 4}, maghemite γ-Fe{sub 2}O{sub 3}, and wustite FeO.
- OSTI ID:
- 22771432
- Journal Information:
- Physics of the Solid State, Vol. 60, Issue 2; Other Information: Copyright (c) 2018 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7834
- Country of Publication:
- United States
- Language:
- English
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