Room-temperature synthesis and characterisation of ion-induced iron-carbon nanocomposite fibres

Graphite plates were Ar+ ion-irradiated with and without a simultaneous Fe supply at room temperature. The surfaces ion-irradiated without an Fe supply were covered with densely distributed conical projections with a carbon nanofibre (CNF) on the top. The CNFs thus grown were 20-50 nm in diameter and 0.3-2 ?m in length. By contrast, the graphite surfaces ion-bombarded with a simultaneous Fe supply were characterised by various kinds of carbon composites, such as conical protrusions with and without a single carbon nanocomposite fibre (CNCF) on the top, depending on the Fe supply rates. As confirmed by transmission electron microscope (TEM),the CNCFs thus grown were amorphous-like and possessed no hollow structure. Energy dispersive X-ray analysis disclosed that CNCFs consisted of carbon and iron, and quite fine Fe crystallites were dispersed over the CNCF.Since various metals can be incorporated into the room-temperature grown carbon nanofibres, this ion-irradiation method is believed to be promising as a new approach to synthesise one-dimensional (1-D) nanomaterials at low temperatures.