Fullerenes and carbon nanotubes are two closely related carbon materials. While fullerenes have bucky-ball structure, carbon nanotubes are stripes of graphite rolled up seamlessly into tubes (cylinders). The carbon atoms in a carbon nanotube are arranged in hexagons, similarly to the arrangement of atoms in a sheet of graphite. The electronic properties of a carbon nanotube are fully determined by its helicity (chirality) and diameter. They can have both metallic and semiconducting properties.

The typical dimensions of a single wall carbon nanotube are: 1 nm in diameter and length of few micrometers. On the other hand, multi-walled carbon nanotubes can have diameters up to 100 nm. Recently, super long carbon nanotubes with length of around 1 cm were successfully synthesized.

Carbon nanotubes are produced by a variety of methods. The most common methods for the production of single- and multi-walled nanotubes include chemical vapor deposition (CVD), electric arc-discharge, laser ablation of a carbon target, etc. Aligned (forest-like) carbon nanotubes can also be synthesized. Aligned carbon nanotubes provide a well-defined structure for some applications. For example, high power density supercapacitors can be built using locally aligned carbon nanotube electrodes.

Carbon nanotubes play important role in the developing field of nanotechnology. Their excellent electronic transport properties make them good candidates for building blocks in nanoelectronics. The high aspect ratio of carbon nanotubes is favorable in applications based on field emission, like flat panel displays and lamps. Furthermore, the strong mechanical properties and high thermal stability of carbon nanotubes improve the properties of matrix materials such as polymers or ceramics. Carbon nanotubes have also been used as an alternative to currently used fillers (e.g. carbon black) to facilitate electrostatic dissipation by increasing the conductivity of polymers. Other studies have been directed towards improving the conductivity of already conducting polymers, thus resulting in a more conductive material.

As already mentioned, the properties of carbon nanotubes are fully determined by their exact atomic structure. Thus, in order to build a precise nanotube-based nanoelectronic device with well-defined properties, it is crucial to control the positioning and the atomic (electronic) structure (helicity) of nanotubes already in the growth phase. Some major hurdles still need to be overcome in this field. However, there are many applications where carbon nanotube networks are used instead of individual nanotubes. In these cases the properties of the whole nanotube network are determinative. These applications are very promising and a long line of nanotube-based materials and devices are already in the pipeline.

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