CNT

CNT most commonly refers to carbon nanotubes, cylindrical nanostructures made of carbon. They are formed by rolling a sheet of graphene into a seamless tube, producing structures with extraordinary strength and unique electrical and thermal properties. Carbon nanotubes were first observed in the early 1990s by Sumio Iijima and have since been the subject of extensive research in materials science and nanotechnology.

There are two main types: single-walled carbon nanotubes (SWCNTs), which consist of a single graphene cylinder, and multi-walled carbon nanotubes (MWCNTs), consisting of multiple concentric graphene cylinders. The electronic behavior of CNTs depends on their chirality (the way the graphene sheet is rolled) and diameter. Some CNTs are metallic, while others are semiconducting, which affects their use in electronic applications. Diameters typically range from about 0.4 to a few nanometers for SWCNTs, with longer lengths and larger diameters possible for MWCNTs.

Key properties include very high tensile strength and Young’s modulus, exceptional electrical conductivity in many cases, and high thermal conductivity. These properties, along with a high aspect ratio, make CNTs attractive for reinforcing materials, conductive films, energy storage electrodes, sensors, and nanoelectronic components. Synthesis methods include arc discharge, laser ablation, and chemical vapor deposition (CVD). Purification and dispersion remain challenges, as CNTs tend to bundle and aggregate, requiring functionalization or specialized processing.

Other uses of the acronym CNT exist, such as the Confederación Nacional del Trabajo, a Spanish anarcho-syndicalist labor union.