Structural and Magnetic Studies of CoFe2 O 4 Ferrite, CoFe2 O 4/CoFe2 Nanocomposites and CoFe2 Nano-alloy
| Autor: | H. M. I. Abdallah, Thomas Moyo, J. Z. Msomi, Itegbeyogene P. Ezekiel |
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| Rok vydání: | 2016 |
| Předmět: |
010302 applied physics
Materials science Alloy Spinel Analytical chemistry 02 engineering and technology Coercivity engineering.material 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Electronic Optical and Magnetic Materials Magnetization 0103 physical sciences Mössbauer spectroscopy engineering Ferrite (magnet) Crystallite 0210 nano-technology High-resolution transmission electron microscopy |
| Zdroj: | Journal of Superconductivity and Novel Magnetism. 30:2371-2374 |
| ISSN: | 1557-1947 1557-1939 |
| DOI: | 10.1007/s10948-016-3849-8 |
| Popis: | Nanoferrite of CoFe2 O 4 was synthesized using the glycol-thermal method at 200 ∘C for 6 h. The nanocomposites and nano-alloy were produced by the reduction of the ferrite using different amounts of activated charcoal at 900 ∘C for 3 h in high-purity flowing argon atmosphere. Complete reduction yields the nano-alloy phase while partial reduction produces the nanocomposites. XRD measurements of the nanoferrite showed a single-phase spinel structure with an average crystallite size of about 10 nm. The CoFe2 nano-alloy was obtained at an activated charcoal molar ratio of n C=6. The HRTEM of all the reduced samples showed clear differences. 57Fe Mossbauer spectra measurements of the reduced samples showed the transformation of the spinel structure to the composite and alloy phase. Mossbauer fits showed that Fe 3+ was reduced to Fe 2+ with lower magnetic hyperfine fields observed in the reduced samples. Magnetization measurements for reduced samples show significant enhancement. The coercivity of the fully reduced samples of the nanoferrite was observed to be less dependent on temperature. |
| Databáze: | OpenAIRE |
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