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Methods for the production of metal–carbon nanoparticles of the core–shell type based on the formation of transition metal nanoparticles and a graphite-like shell on their surface containing to 50 graphene layers are considered. Various types of high-energy impacts or thermal transformations under exposure in a temperature range of 600–850°С were used for the synthesis of metal–carbon nanoparticles from initial metal- and carbon-containing components. Due to their unique properties, nanoparticles of this kind can be of interest as highly efficient catalysts, targeted drug carriers, contrasts in MRI diagnostics, and an element base of electronic and magnetic devices.

A method for the synthesis of metal–carbon nanocomposites in which metal-centered particles of the core–graphite-like shell type are distributed in the bulk of an amorphous sp2-carbon matrix is proposed. Polyvinyl chloride (PVC) was used as a carbon matrix precursor. The synthesis procedure included the following stages: The dehydrochlorination of PVC with diethylamine in a dimethyl sulfoxide solution in the presence of Co, Ni, Fe, or Cu nitrates; the carbonization of the product at 400°C; metal reduction with hydrogen at 500–620°C; and methane conversion at 620–850°C. The metal concentrations in the resulting composites were the following (%): Fe, 10; Ni, 10.8; Co, 11; and Cu, 21. The structure of the final metal–carbon nanocomposites was studied by transmission electron microscopy. The size of a metal core was 20–100 nm, and the number of graphene layers in a shell was to 50.

It was shown that methane decomposition on metal–carbon nanocomposites with transition metal (Co, Fe, and Ni) nanoparticles distributed in the bulk of the amorphous carbon matrix leads to carbon deposition with the formation of a graphite-like shell around a metal core. The resulting “core-shell” structures have a diameter of 10–40 nm and contain up to 50 graphene layers with an interlayer distance of 0.34–0.35 nm. For the synthesis of the initial metal–carbon nanocomposites, a method that we proposed earlier was used, which involves low-temperature formation of carbon structures from carbon-chain chloropolymers based on their dehydrochlorination with the formation of polyvinylenes as reactive carbon precursors.

A method for carbon materials synthesis based on polyvinyl chloride has been proposed. Method includes polymer dehydrochlorination by alkali with carbon-rich conjugated structures (polyvinylenes) formation and its subsequent carbonization at relatively low temperatures. Raman and 13C NMR spectroscopy and transmission electron microscopy show that thermal treatment of the resulting polyvinylenes up to 400 °C leads to the formation of amorphous carbon material with chlorine contain less than 0.5 wt.%. These results can be used to develop dioxin-free technology of utilization of polyvinyl chloride and its wastes.

A method for the synthesis of core-shell structures during methane decomposition in a cobalt-carbon composite with metal particles uniformly dispersed in its bulk is proposed. These composites are obtained by the low-temperature formation of carbon structures based on reactive conjugated polymers obtained by the dehydrochlorination of chlorine-containing carbon-chain polymers. Eelectron microscopy studies show the formation of structures containing 10–50 graphene layers closely packed around a metal core with an interlayer distance of 0.34–0.35 nm.

A comparative study of the effect of a high-power ion beam of nanosecond duration on layers of reactive industrial chlorinated polymers (chlorinated polyvinyl chloride, polyvinyl chloride) containing a catalytic additive (ferrocene) is carried out. The formation of amorphous carbon nanofiber layers on the surface of chlorinated polymers is revealed. The characteristic diameter and length of nanofibers depends on the type of polymer and irradiation mode and is equal to 30–250 nm and 10 μm, respectively. The growth rate of carbon nanofibers is estimated. Its value might reach ~160 μm/μs. A possible mechanism for carbon nanofiber formation on the surface of chlorinated polymers with the addition of ferrocene under high-power ion beam irradiation is discussed.

The effect of a nanosecond high-power ion beam on thin polymer layers of chlorinated polyvinyl chloride and polymethyl methacrylate containing ferrocene as an additive is investigated. Arrays of carbon nanofibers with a characteristic diameter of 30–160 nm and lengths of up to 15 m are formed on the surface of the chlorinated polyvinyl chloride. The same effect on polymethyl-methacrylate layers leads to intense cavitation of the surface layer. The possible mechanisms of the formation of carbon nanofibers in chlorinated polyvinyl chloride with ferrocene additive under the action of a high power ion beam are discussed.

Mechanochemical activation of PVC in a high-energy centrifugal-planetary mill was shown to increase its reactivity in dehydrochlorination under the action of bases. Thus modified PVC is capable of low-temperature carbonization and can form a carbon material even at the temperatures below 400°C.

The surface morphology and the composition of polymer layers based on chlorinated polyvinylchloride with addition of ferrocene (up to 10% of the polymer mass) subject to the action of a nanosecond high-power ion beam are studied. It is demonstrated that carbon material in the form of nanofibers with an average diameter of 80 nm and a length of up to 10 μm is formed on a surface singly irradiated by such beam with a current density of ∼100 A/cm2. A possible mechanism of the observed phenomenon is discussed.