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Updated: Nov 8, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Study of Soft/Hard Bimagnetic CoFe²/CoFe²O⁴ Nanocomposite.
E H Coldebella1, E F Chagas1, A P Albuquerque1
1Instituto de Física, Universidade Federal de Mato Grosso, Av. Fernando Correa da Costa, 2367, 78060-900 Cuiabá-MT, Brazil.
Journal of Nanoscience and Nanotechnology
|April 20, 2021
Summary
This study details the creation of novel bimagnetic nanocomposites, CoFe₂/CoFe₂O₄, via controlled reduction and oxidation processes. The resulting materials exhibit coupled magnetic behavior, indicating potential for advanced magnetic applications.
Area of Science:
- Materials Science
- Nanotechnology
- Magnetism
Background:
- Bimagnetic nanocomposites offer tunable magnetic properties.
- Controlling phase composition is crucial for desired magnetic behavior.
- Understanding inter-phase magnetic coupling is key for advanced applications.
Purpose of the Study:
- To synthesize and characterize CoFe₂/CoFe₂O₄ bimagnetic nanocomposites.
- To investigate the effects of thermal treatment on material formation and magnetic properties.
- To evaluate the influence of high energy milling on the magnetic characteristics.
Main Methods:
- Stoichiometric combustion method for precursor CoFe₂O₄ synthesis.
- Controlled thermal treatment (reduction in H₂, oxidation in O₂) to form CoFe₂/CoFe₂O₄.
- Characterization using X-ray diffraction, Mössbauer spectroscopy, and transmission electron microscopy.
- Magnetic hysteresis measurements to determine saturation magnetization and magnetic behavior.
Main Results:
- Formation of CoFe₂/CoFe₂O₄ nanocomposites confirmed by XRD, Mössbauer spectroscopy, and TEM.
- Saturation magnetization varied from 87 to 108 emu/g, correlating with CoFe₂O₄ content.
- Single magnetic behavior observed in hysteresis curves, indicating strong magnetic coupling between CoFe₂ and CoFe₂O₄ phases.
- High energy milling was evaluated for its impact on magnetic properties.
Conclusions:
- Successfully synthesized CoFe₂/CoFe₂O₄ bimagnetic nanocomposites with tunable magnetic properties.
- Demonstrated magnetic coupling between the constituent phases, suggesting potential for enhanced magnetic performance.
- The synthesis route provides a method for creating advanced magnetic nanomaterials.
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