Nanotubes, or Carbon Nanotubes (CNTs), are one of the main nanomaterials applied in nanotechnology research and development. These Nanotubes are composed of carbon atoms connected in a cylindrical shape and have either open ends or close ends. CNTs can measure down to 1nanometer and up to several centimeters of length and diameter. There are two types of carbon nanotubes, 1- Single-walled nanotubes (SWNTs) and 2- Multi-walled nanotubes( MWNTs).
A hybrid of Graphene and Nanotubes exists since recently. The hybrid structure consists of graphene layers rolled along the sidewalls of a Multi-walled nanotube.
The different types of CNTs are used in many fields such as in biological, electronical, mechanical, optical, textile and space applications. Within these fields, the carbon nanotubes can be used as semiconductors, thermal conductors, filters, lightweight strong material replacement among others.
Besides current CNTs applications, in the far future, a tether will be manufactured by several nanotubes to create a transportation method between the Earth’s surface and a space station.