Branching carbon nanotubes deposited in HFCVD system

Branching carbon nanotubes were deposited as a by-product of diamond thick films in a hot filament chemical vapor deposition (HFCVD) system using acetone and hydrogen. The branching nanotubes were observed to be uniformly 'Y' shaped. Electron diffraction pattern (EDP) and Raman scattering analysis showed that the nanotubes were well graphitized. A broadened graphite (0002) diffraction spot in EDP from the nanotube 'Y' junction was also observed as a result of negative curvature surfaces. Energy dispersive X-ray (EDX) analysis indicated that the nanotubes contained a small amount of Cu, which originated from the parts near the hot filaments. The Cu is believed to have acted as a catalyst for the large production of the branching carbon nanotubes. (C) 2000 Elsevier Science S.A. All rights reserved.