Bayer, B.C.; Castellarin-Cudia, C.; Blume, R.; Steiner, S.A.; Ducati, C.; Chu, D.; Goldoni, A.; Knop-Gericke, A.; Schlögl, R.; Cepek, C.; Robertson, J.; Hofmann, S.: Tantalum-oxide catalysed chemical vapour deposition of single- and multi-walled carbon nanotubes. RSC Advances 3 (2013), p. 4086-4092
10.1039/c3ra23304a
Open Access Version (externer Anbieter)
Abstract:
Tantalum-oxide thin films are shown to catalyse single- and multi-walled carbon nanotube growth by chemical vapor deposition. A low film thickness, the nature of the support material (best results with SiO2) and an atmosheric process gas pressure are of key importaance for successful nanotube nucleation. Strong material interactions, such as silicide formation, inhibit nanotube growth. In situ X-ray photoelectron spectroscopy indicates that no catalyst reduction to Ta-metal or Ta-carbide occurs during our nanotube growth conditions and that the catalytically active phase is the Ta-oxide phase. Such reduction-free oxide catalyst can be technologically advantageous.