Carbon nanostructures (CNS) were synthesized by the electric arc plasma chemical method during the evaporation of a high-quality graphite electrode of the brand “fine-grained dense graphite” (FGDG-7) filled with a catalyst (Pt), which was evaporated in a helium environment. In the synthesis process, the following were synthesized: multi-walled (MWCNT) and single-walled carbon nanotubes (SWCNT), fullerenes, graphene packets and nanocomposites. A deposit in the form of growth on the cathode electrode was also synthesized. All synthesis products were analyzed at the micro- and nanolevels, which made it possible to analyze the influence of platinum vapors on the formation of carbon nanomaterials (CNM). The non-uniform distribution of catalyst atoms (platinum) in the products of electrochemical synthesis in a gas medium using FGDG-7 graphite was investigated. During the analysis, it was found that platinum is in the state of the face-centered cubic (FCC) lattice and is distributed in the synthesis products as follows: the core of the deposit is less than < 0.001 %, the shell of the deposit is less than < 1 %, the wall soot is more than > 1 %. The morphology and composition of the platinum deposit, which has a hexagonal graphite structure with an admixture of a rhombohedral graphite phase, was studied. In the studies, differential thermal analysis in air (TG, DTG, DTA) was carried out, which made it possible to identify the composition of the synthesis products. It is an established fact that the parts of the deposit with platinum are more heat-resistant compared to the deposit components that do not contain Pt. The resulting carbon nanotubes (CNTs) in diameter (5–25 nm) and length (1.5–2 μm) do not differ from those obtained without the participation of platinum, except for some anomalies. When studying the suitability of platinum-containing carbon nanostructures for 3D printing of CJP (ceramic printing) technology, it was found that for the use of platinum-containing carbon black, it is necessary to carry out a preliminary short-term treatment, namely, grinding in special “ball mills” or rubbing through a fine sieve with minimal effort to create uniformity product. Previous studies have shown that such platinum-containing carbon nanostructures can already be used in 3D printing of CJP technology, or to create new composites for 3D printing technologies of FDM, SLA.

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In the work, carbon nanostructures (CNS) were synthesized on a plasma chemical plant using graphite electrodes SIGE (Special Impregnated Graphite Electrodes) and FGDG-7 (Fine-grained dense graphite) in a helium environment. In the experiments, it was established that graphite electrodes of the SIGE brand are suitable for the synthesis of CNS by the electric arc plasma chemical method. In addition, the experiments indicate that SIGE graphite in electric arc synthesis in a gas environment allows the creation of centimeter composite rods (deposits), where the core consists of graphene sheets rolled into nanotubes that can withstand extremely high temperatures (>4000 K). Studies using scanning microscopy have shown that the synthetic deposit of SIGE graphite can be divided into blocks, which is important for its use in high voltage stations because it is possible to prepare deposits of the required length without mechanical impact and without violating the integrity of its structure. The structure of the synthesized carbon materials was studied by scanning and transmission electron microscopy and it was shown that carbon nanotubes are formed during the evaporation of SIGE brand graphite even without the use of a catalyst. Experiments have confirmed that the mass yield of wall fullerene-containing carbon black during the evaporation of SIGE grade graphite significantly exceeds the results obtained during the evaporation of FGDG-7 grade graphite electrodes. Such results make SIGE graphite more productive for the synthesis of expensive carbon nanoproducts (fullerenes and fullerene-like structures) by the electric arc method. It was also recorded that during the synthesis of carbon nanostructures, single-walled carbon nanotubes are formed, which have a positive charge and are deposited in the form of a core on the surface of the cathode electrode under the action of an electromagnetic field.

A review of more than 100 contemporary literary works of domestic and foreign researchers on the issues of electric arc synthesis (EAS) of various carbon nanostructures (CNS) has been performed. EAS CNScan be performed in both gaseous and liquid media. EAS in a gaseous medium has a number of advantages, such as high productivity and velocity of the condensation process, as well as ease of control.But this method of synthesis also has disadvantages: it requires a complex vacuum and cooling system, which makes the installation very cumbersome.In addition, this method does not solve the problem of agglomeration of synthesized CNS and has a by-product of synthesis in the form of growth (deposit) on the electrode. EAS in a liquid medium is more compact equipment, as it does not require systems of vacuum (the process takes place at atmospheric pressure) and cooling (liquid medium plays the role of heat dissipation).This method of synthesis uses different types of dielectric liquids – from distilled water (H2O), liquid nitrogen (N2) to hydrocarbon solvents, which can serve as a source of carbon in the synthesis zone.By changing the composition of the liquid phase, it is possible to achieve the synthesis of different types of CNS.Also, this method involves the use of metal electrodes, which, in addition to long service life, can act as catalysts.The metal particles can be encapsulated ANS, forming composites with different magnetic properties.In some studies, it has been shown that mixtures of metal carbides can be formed when metal electrodes are used in the EAS process in a liquid medium.The liquid medium after EASCNS is also of scientific interest. Probably, the liquid medium contains new modifications of soluble organic compounds, which are being researched by researchers around the world.Thus, scientists have found that after EAS in a liquid medium using graphite electrodes, the working solution (C6H6) changed its color.This indicates the formation of soluble organic compounds in it. In the literature review on the basis of literature data the table of modes for industrial synthesis of single-walled CNS is created.Also, a list of modes for the creation of defective CNS as a method of increasing the area of adsorption in nanoparticles. The solution of important problems of the EAS method is recorded: agglomeration of CNS; the problem of forming a deposit; increase productivity.

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