Growth valley dividing single- and multi-walled carbon nanotubes: combinatorial study of nominal thickness of co catalyst

Kazunori Kakehi, Suguru Noda, Shigeo Maruyama, Yukio Yamaguchi

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23 Citations (Scopus)


The relationships among the nominal thickness of Co catalysts, the structure of the catalyst particles, and the structure of carbon nanotubes (CNTs) growing from the catalysts were investigated. A gradient thickness profile of Co was prepared using a combinatorial method and then subjected to alcohol catalytic chemical vapor deposition at 700 °C. In the deposited sample, two active regions appeared on either side of an inactive region. In the active regions, mainly single-walled carbon nanotubes (SWNTs) or multi-walled carbon nanotubes (MWNTs) grew, depending on the nominal Co thickness (SWNTs grown at a Co thickness of about 0.1 nm, and MWNTs grown at a Co thickness of about 1.5 nm). However, neither SWNTs nor MWNTs grew efficiently at a moderate Co thickness (∼0.4 nm). This dependence of CNT growth on the initial Co thickness is explained by the different mechanisms of catalyst particle formation from sub-nanometer-thick and nanometer-thick Co films.

Original languageEnglish
Pages (from-to)1961-1965
Number of pages5
JournalJapanese Journal of Applied Physics
Issue number4 PART 1
Publication statusPublished - 2008 Apr 18
Externally publishedYes



  • Catalytic growth mechanism
  • Chemical vapor deposition
  • Combinatorial method
  • Ethanol
  • Multi-walled carbon nanotubes
  • Nanoparticle formation
  • Single-walled carbon nanotubes

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

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