Homogeneous carbon nanotubes (CNTs) of high quality are prepared by substrate based chemical vapour deposition using either gas phase prepared metal nanoparticles or sputtered thin films. The use of gas phase prepared nanoparticles allows the production of individual and pure catalyst particles with a narrow particle size distribution. Sputtered thin films, on the other hand, allow the production of CNT with high yield. If deposited onto appropriate substrates these nanoparticles or thin films (that break up upon heating), respectively, can act as individual nucleation sites for the growth of carbon nanotubes. As the nanoparticle deposition system allows for control of particle density, particle size and size distribution this approach provides simultaneous control over the density and the diameter distribution of the resulting CNTs. Furthermore the separation of catalyst preparation and CNT growth allows for the independent monitoring and optimization of either process.
Metastable and Nanostructured Materials
Tailoring the CNT's diameter and number of walls
Large scale overview TEM micrograph of the as grown CNT network(a). CNT with a FeNi particle at the top attached to the TEM carrier film (b).