Abstract
Nanoparticles can also be used as catalysts due to their high surface area. Of course, catalytic properties also occur in certain dimensions like magnetic properties. In other words, nanoparticles usually have catalytic properties if their specific surface is between 100 and 400 square meters per gram. Therefore, among nanoparticles with a specific volume, a nanoparticle with a larger surface area shows better catalytic properties. An example of nanoparticles that act as catalysts where various substances are placed on their surface and chemical reactions are carried out. Apart from the mentioned cases, nanoparticles have many other applications in various medical industries (drug delivery, etc.), automobiles (anti-fogging windows, lightening the body, strengthening tires), electronics (making transistors), etc. The strength of carbon-carbon bonds gives carbon nanotubes amazing electronic properties. No previous material exhibits the extraordinary combination of mechanical, thermal and electronic properties attributed to them . However, their conductivity is what sets them apart. Multi-layered carbon nanotubes are the strongest materials that mankind has discovered so far in terms of electronic conductivity. The highest tensile strength or breaking strain for a carbon nanotube was up to 63 GPa, which is about 50 times more than the strongest conductors. Even the weakest types of multi-layered carbon nanotubes have multifold power in electronic conduction. These properties, along with the lightness of carbon nanotubes, give them great potential in applications such as aerospace. The electronic properties of the wall of carbon nanotubes are also extraordinary. It has high electrical conductivity (comparable to copper). It is particularly noteworthy that nanotubes can be metallic or semiconducting. The rolling action breaks the symmetry of the planar system and imposes a specific direction with respect to the hexagonal grid and the axial direction. Depending on the relationship between these axial directions and the unit vectors that describe the hexagonal lattice, nanotubes may behave electrically like metals or semiconductors , with some nanotubes having higher conductivity than copper, while Others behave more like silicon . And there are possibilities of making nano electronic devices from multi-layer nanotubes of CNTs.