Nano - onion or onion form of carbon ( nano-onion or nested nanoparticle ) is a nanoscale carbon structure formed by carbon spheres nested in each other.
Description
When detonation nanodiamond is heated in an inert atmosphere ( nitrogen , helium ) or in vacuum up to 900 o C, a gas of complex composition containing mainly CO 2 , N 2 and CH 4 is released . At higher temperatures, graphitization of nanodiamond begins - the transition of nanodiamond to graphite , as a rule, is also nanoscale (the so-called nanographite). The intermediate stage in this process is the onion form of carbon. Nanodiamonds rebuild their structure, forming carbon spheres nested in each other - a nanomatrix - a carbon onion, or multilayer fullerene . In turn, this onion form of carbon under the action of an electron beam can again be rearranged into nanodiamond. In the presence of a massive catalytic phase (for example, graphite) and without exposure to an electron beam, carbon bulbs deform over time and collapse.
The possibility of the formation of closed conductive layers of onionic carbon on the surface of 4–5 nm nanodiamond particles during thermal or electron beam annealing opens up prospects for creating electronic structures with quantum dots suitable for switching electrical signals, detecting and generating electromagnetic radiation .
Literature
- Vul Ya., Aleksenskiy AE, Dideykin AT: Detonation nanodiamonds: technology, properties and applications // Nanosciences and Nanotechnologies in Life Cycle Support Systems. - Oxford, UK, 2009. (English)
- Rekhviashvili S.Sh., Bukhurova MM The stability of carbon nano-onions in contact with a graphite substrate // Letters to the Journal of Technical Physics. 2019. T.45. №12. C.9-11.