학술논문
A study of the magnetic and electromagnetic properties of γ-Fe2 O3 –multiwalled carbon nanotubes (MWCNT) and Fe/Fe3 C–MWCNT composites
Document Type
Article
Source
Subject
*CARBON nanotubes
*FERROMAGNETIC materials
*ELECTROMAGNETISM
*IRON oxides
*EMULSIONS
*ANISOTROPY
*TRANSMISSION electron microscopy
*X-ray diffraction
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Language
ISSN
0254-0584
Abstract
Abstract: A ferromagnetic γ-Fe2O3–MWCNT composite was prepared by a reverse microemulsion technique, and was transformed to a Fe/Fe3C–MWCNT composite by further heat-treatment in H2 atmosphere at 950°C. TEM result suggests that MWCNTs are both surface decorated and filled with γ-Fe2O3 or Fe/Fe3C nanoparticles. The saturation magnetization and anisotropy field are particularly strong for Fe/Fe3C–MWCNT. The reflection loss of Fe/Fe3C–MWCNT is better than that of γ-Fe2O3–MWCNT at all frequencies between 2 and 18GHz, resulting from enhanced magnetic loss and better matched characteristic impedance, rather than electric loss, as shown by the complex relative permeability and permittivity . The microwave absorbing properties can be modulated simply by manipulating the thickness of the prepared Fe/Fe3C–MWCNT composite for application in different frequency bands. [Copyright &y& Elsevier]