Synthesis and Characteristics of Fe3C Nanoparticles Embedded in Amorphous Carbon Matrix

We proposed a new way to synthesize a nanocomposite consisted of cementite Fe3C nanoparticles and amorphous carbon by radio frequency plasma-enhanced chemical vapor deposition. Transmission electron microscope images show the existence of nanometric dark grains(Fe3C) embedded in a light matrix(amorphous carbon) in the samples. X-ray photoelectron spectroscopy experiment exhibit that the chemical bonding state in the films corresponded to sp(3)/sp(2) amorphous carbon, sp(3)C-N(287.3 eV) and C-1s, in Fe3C(283.5 eV). With increasing deposition time, the ratio of amorphous carbon increased. The magnetic measurements show that the value of in-plane coercivity increased with increasing carbon matrix concentration(from about 6.56x10(3) Aim for film without carbon structures to approximately 2.77x10(4) and 5.81x10(4) A/m for nanocomposite films at room temperature and 10 K, respectively). The values of saturation magnetization for the synthesized nanocomposites were lower than that of the bulk Fe3C (140 Am-2/kg).