Formation and growth mechanisms of ion-induced iron–carbon nanocomposites at room temperature

The irradiation of graphite surfaces with a simultaneous Fe supply have resulted into the development of various types of carbon nanocomposites. Their morphologies – diameter, density, length and apex angle strongly depend on the ratios of Fe deposition rate (DFe) to ion sputtering rate (Sion). By optimizing the ratio of DFe/Sion (2.40%), the denser and well-aligned Fe–carbon nanocomposite fibers (Fe–CNFs) could be obtained, whose average length and diameter were 0.95 μm and 17 nm, respectively. As confirmed by energy-dispersive X-ray analysis, the Fe–CNFs with amorphous-like or fine-polycrystalline phase were surely composed of carbon and Fe. Two types of growth models have been employed to explain the formation of metal–carbon nanocomposites.