Carbon nanotubes

A carbon tube with a diameter commonly measured in nanometers is known as a carbon nanotube (CNT). One type of carbon allotrope, single-wall carbon nanotubes (SWCNTs), are nanometer-sized tubes that are midway between fullerene cages and flat graphene. Single-wall carbon nanotubes can be envisioned as cuttings from a two-dimensional hexagonal lattice of carbon atoms that have been rolled up along one of the Bravais lattice vectors to create a hollow cylinder, even though they are not really manufactured in this way. A helical lattice of flawlessly connected carbon atoms is produced on the cylinder surface in this construction by imposition of periodic boundary constraints throughout the length of this roll-up vector. Van der Waals weakly bonded single-wall carbon nanotubes nested together to form multi-wall carbon nanotubes (MWCNTs) composed of stacked single-wall carbon nanotubes that are only loosely connected to one another by van der Waals forces. These tubes resemble the long straight and parallel carbon layers cylindrically stacked around a hollow tube proposed by Oberlin, Endo, and Koyama, though not identically. It is also common to refer to double- and triple-wall carbon nanotubes as multi-wall carbon nanotubes. The phrase "carbon nanotubes" can also refer to tubes having a carbon wall structure that is unknown and sizes under 100 nanometers. Radushkevich and Lukyanovich found these tubes in 1952. The diameter of the carbon nanotube created using popular manufacturing techniques is often significantly greater than its diameter, however this is not always stated. As a result, end effects are frequently disregarded and it is thought that carbon nanotubes have an endless length. While some carbon nanotubes are semiconductors, others can display extraordinary electrical conductivity. Because of their nanostructure and the strength of the connections between the carbon atoms, they also exhibit outstanding tensile strength and thermal conductivity. They can also undergo chemical modification. These characteristics are anticipated to be useful in a variety of technological fields, including electronics, optics, composite materials (replacing or enhancing carbon fibres), nanotechnology, and other materials science-related applications.