Carbon Nanotubes – Quantum Wires to Artificial Muscles

Carbon nanotube research, whilst still in its infancy, has come a long way since their discovery in 1991. Considerable characterisation work is still to be done on nanotubes, however this requires a reliable production method of the raw material in sufficient volumes to enable thorough experimental analysis. As part of his fullerene research, fullerenes being of the same carbon family as carbon nanotubes, Wolfgang Kraetschmer made a major breakthrough in synthesis technology in 1990, with the resultant device now bearing his name and being used in nanotechnology research groups around the world. Fullerene, C60, is a nearly spherical molecule composed of 60 carbon atoms arranged in pentagons and hexagons, like a soccer ball. Fullerenes are molecules with a well determined finite size (0.71nm for C60). Nanotubes, on the other hand, are tiny needle-like structures. A nanotube can be considered as a seamless roll of a graphene sheet, with a typical diameter of 1nm and lengths up to microns. Nanotubes are molecules in their cross section, but along the axis they are infinite solids. Nanotube physics is an interesting superposition of molecular physics in the cross section and solid state physics along the axis.