Room-temperature growth of ion-induced carbon nanofibers: Effects of ion species

Graphite surfaces were bombarded with Ne⁺, Ar⁺ and Xe⁺ ions at 450 eV-1 keV to induce the carbon nanofiber (CNF) growth at room temperature, and the dependence of size and numerical density of ion-induced CNFs on the ion species and ion energy was investigated in detail. The ion-sputtered surfaces were covered with densely distributed conical protrusions and aligned CNFs grew on the tips, except for the low-energy Xe⁺-sputtered surfaces. Longer CNFs grew by lighter-mass-ion irradiation, and finer CNFs formed by heavier-mass-ion bombardment. In addition, the higher the ion energy, the longer the length of the ion-induced CNFs. Because the size and numerical density were controllable by the ion-irradiation parameters, ion-induced CNFs were believed to be quite promising for myriad of applications such as high-resolution scanning probe microscope cantilevers, bio-cell manipulators and field emission source operating at low voltage.