Surface-bound chemical vapour deposition of carbon nanotubes: In situ study of catalyst activation

✍ Scribed by C. Mattevi; S. Hofmann; M. Cantoro; A.C. Ferrari; J. Robertson; C. Castellarin-Cudia; S. Dolafi; A. Goldoni; C. Cepek

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 561 KB
• Volume: 40
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/j.physe.2007.10.024

✦ Synopsis

We combine in situ X-ray photoelectron spectroscopy and ex situ electron and Raman spectroscopy to study chemical interactions of SiO 2 -supported Fe catalyst films during C 2 H 2 exposure in the 400-600 1C temperature range. Carbon nanotubes nucleate at C 2 H 2 pressures below 10 À6 mbar, which allows a time-resolved recording of core level spectra. We find a rapid transition from an initial chemisorbed carbon on metallic Fe catalyst nanoparticles to a sp 2 graphitic carbon network. Pre-treating the Fe catalyst film by H 2 sputtering influences the initial catalyst de-wetting and increases carbon nanotube yield.