Well-aligned graphitic nanofibers synthesized by plasma-assisted chemical vapor deposition

Well-aligned graphitic nanofibers on a large scale have been grown on Ni(100) wafers by plasma-assisted hot filament chemical vapor deposition using a mixed gas of nitrogen and methane. A two-stage control of the plasma intensity has been used in the nucleation and growth stages of the fibers. The growth direction of the fibers is perpendicular to the substrate surface and the plasma-induced Ni particles serve as a catalyst. The diameter of the fibers is in the range 50–500 nm, mostly between 100–200 nm, controlled by the size of the nickel particles. The growth mechanism of the fibers is described based on structural information provided by scanning electron microscopy and transmission electron microscopy.