A study of the magnetic and electromagnetic properties of γ-Fe2O3–multiwalled carbon nanotubes (MWCNT) and Fe/Fe3C–MWCNT composites
A study of the magnetic and electromagnetic properties of γ-Fe2O3–multiwalled carbon nanotubes (MWCNT) and Fe/Fe3C–MWCNT composites
复制标题
DOI：
10.1016/j.matchemphys.2008.10.010
复制
发表时间：
2009-04
影响因子：
4.6
通讯作者：
Ping Xu;Xiuli Han;Xiaoman Liu;Binggang Zhang;Changyong Wang;Xiaohong Wang
中科院分区：
文献类型：
--
作者：
Ping Xu;Xiuli Han;Xiaoman Liu;Binggang Zhang;Changyong Wang;Xiaohong Wang
采用反相微乳液技术制备了铁磁γ-Fe2O3-MWCNT复合材料，并在950℃的H2气氛中进一步热处理转化为Fe/Fe3C-MWCNT复合材料。 TEM 结果表明，MWCNT 表面装饰并填充有 γ-Fe2O3 或 Fe/Fe3C 纳米颗粒。 Fe/Fe3C-MWCNT 的饱和磁化强度和各向异性场特别强。在 2 至 18GHz 之间的所有频率下，Fe/Fe3C-MWCNT 的反射损耗均优于 γ-Fe2O3-MWCNT，这是由于增强的磁损耗和更好匹配的特性阻抗（而不是电损耗）造成的，如复数相对磁导率 [公式：见正文] 和介电常数 [公式：见正文] 所示。通过控制制备的 Fe/Fe3C-MWCNT 复合材料的厚度，可以简单地调节微波吸收性能，以应用于不同的频段。
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 H2atmosphere at 950°C. TEM result suggests that MWCNTs are both surface decorated and filled with γ-Fe2O3or 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 [Formula: see text] and permittivity [Formula: see text] . 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.