Vertically aligned carbon nanotubes (CNTs) were synthesized from Ni nanoparticles prepared by ion implantation. Ni ions were implanted at 30 keV into thermally grown SiO2 substrates using a focused-ion-beam. High-density nanoparticle formation was investigated with high doses up to 5.0 × 1017 ions/cm2. Dense Ni nanoparticles in the order of 1011-1012 cm- 2 were obtained on a SiO2 substrate, and the particle density and diameter were controlled by post-implantation annealing. Particles annealed at 700 °C led to vertically aligned CNTs. Interestingly, catalysts were longer along the vertical axis and the lower half of the Ni particle was buried in SiO2.
ASJC Scopus subject areas
- 化学 (全般)