A system for controlling the process of the high-voltage high-frequency electric discharge synthesis of nanocarbon on metal surfaces in a carbon gas medium has been developed. The criteria that determine the production mode of the synthesis of nanocarbon are defined. The synthesis control is performed according to the minimax optimality criterion. It allows the current value in the range of the production mode of the synthesis of carbon nanomaterials with an onion-like structure to be maintained. The control of the movement of the metal surface sample with respect to the electrode in the course of synthesis ensures the uniformity of coating the surface with a layer of a synthesized nanocarbon material.
The properties of carbon nanomaterials, produced with the help of the method for the high-frequency electrodischarge processing of hydrocarbon gases, based on the creation of non-equilibrium plasma under variation of frequency and treated gas, have been studied. It is shown that the synthesis of onion-like structures and globular carbon nanoparticles with turbostratic structure is possible, depending on the type of gas.
A new method for electrodischarge synthesizing nanocarbon has been elaborated, which provides high gradients of temperatures and pressure at the expense of a high rate of energy input into the plasma channels. The morphological structure of the produced nanocarbon is uniform, the characteristic dimensions of the particles are in the range from 9 to 50 nm, and the content of chemically pure carbon amounts up to 97% (with the balance being O 2 ), so it is possible to avoid the labor-consuming operation of clearing nanocarbon when producing it through the electrodischarge method.
Comprehensive studies of a structure of carbon nanomaterials (CNM) fabricated by the methods of electric-discharge treatment from carbonaceous gases, namely, by a high-voltage electrical breakdown of the dielectric medium and a high-frequency discharge in gases, are carried out. Dependence of the CNM structure on the chemical nature of used carbonaceous gases is revealed.
