This paper describes various compositions of electrically conductive pastes based on polyvinyl chloride, which are suitable for screen printing technology. These pastes are composite systems consisting of finely dispersed particles of a conductive filler, specifically various carbon modifications. These carbon particles are uniformly dispersed within a polymer binder. Electrically conductive carbon pastes therefore consist of three main components: the conductive carbon filler, the polymer binder, and a solvent. Other modifying or stabilizing additives can also be used in the paste, depending on the specific application. The paper investigates the optimal ratio of these componentsAin pastes, specifically between the selected polymer binder (polyvinyl chloride) and the total amount of carbon fillers (graphite and carbon black). This allows to obtaine relatively high-quality electrodes with low electrical resistance. To further search of the minimum possible electrical resistivity value at the selected polyvinyl chloride concentration, an additional set of experiments was conducted with varying ratios of both carbon fillers. The results of a comparative analysis of the surface of the manufactured electrodes using scanning electron microscopy are presented, showing the difference in coating quality based on the composition. It is demonstrated that, in order to meet the required objectives, it is possible to produce electrically conductive carbon pastes with specific properties. Factors that lead to defects affecting both the screen printing process and final printed products are discussed. A unique graph illustrating the correlation between the possibility of screen printing the developed electrically conductive carbon paste and the final electrical resistivity values of the electrodes based on them is provided.

A method is proposed for increasing the resistance of a superhydrophobic coating based on a CNT xerogel to frost deposition through the use of decorating nanoparticles. The effects of the addition of fullerenes, carbon nanoonions (CNOs), detonation nanodiamonds, silicon dioxide, and paraffin to the xerogel are tested. An increase in the resistance of the coating to the deposition of condensate in the form of frost is revealed. The addition of fullerene C 60 leads to the best results. Increasing the resistance to icing allows us to spend less power on heating the surface during short cold snaps, bypassing the anti-icing properties of the protective superhydrophobic layer. However, the application of this approach shows a deterioration in the resistance of the coating to the penetration of the spray. This is given a qualitative explanation and measures to combat it are proposed. No effect of the additives on the mechanical properties of the coating or its resistance to damage is detected. In additon, decorating additives affect the formation of the coating relief. With this, it is possible to influence the stochastic processes of the formation of roughness during the drying of the xerogel.

This paper presents the graphite-based paste, within which an exfoliated graphite as the main electrically conductive component was selected. The resulting graphite-based paste is a ho-mogenous polyvinyl chloride mixture containing carbon materials with different particle sizes (such as gas soot and microcrystalline graphite). The preparation of electrical conductivity graph-ite-based paste and electrode sample based on it and obtained by means of screen printing technol-ogy. The purpose of electrode properties exploration is to elucidate its applicability as a main com-ponent of electrochemistry biosensor for glucose concentration measurements in blood. The results of a comparative analysis of printed electrodes based on it with electrodes made of commercial graphite paste from one of the world's leading manufacturers (Gwent Electronic Materials) are presented. The obtained electrodes were characterized by comparable physical and electrochemical parameters. According to the results of scanning electron microscopy of electrodes, graphite paste with exfoliated graphite is suitable for screen printing. The electrical resistivity of the electrodes with exfoliated graphite was 440 (Ohms center dot mm2)/m, and the electrodes obtained on the basis of com-mercial paste - 270 (Ohms center dot mm2)/m. The biosensor, made on the basis of the original graphite paste, is characterized by a wide range of linearity of response to glucose in the range from 1 to 40 mM, and similar values of currents and sensitivity compared to a commercial analogue. The results of studies of the obtained electrodes have shown that exfoliated graphite is a promising material for use in electrochemical systems, and reducing the concentration of carbon conductive components can significantly reduce the cost of finished graphite paste and increase its commercial potential.

Carbon fibers (CF) were formed from carbon nanotube-doped isotropic petroleum pitch. Ultra-long (the length of a single filament is more than 10,000 nm) double-walled carbon nanotubes (DWCNT) were used for doping in concentrations from 0.1 to 1.0 wt.%. The produced CF were investigated both in pristine and graphitized form. Physical properties (electrical resistivity, thermal conductivity coefficient), as well as X-ray diffraction (XRD) analysis and Raman spectroscopy of obtained DWCNT-doped CF were investigated. The influence of DWCNT concentration on the properties is nonlinear due to the influence on the CF molding mode and heterogeneity of the DWCNT distribution in the filament body. An increase in the DWCNT concentration, on the one hand, causes an enhancement in the thermal conductivity coefficient, and a decrease in the electrical resistivity of the fibers, on the other hand, it leads to local inhomogeneities formation in the material structure («gas bubbles»), as well as distortions of the CF outer surface. An increase in the DWCNT concentration also leads to an increase in CF average diameter and hollow filaments formation. This feature is paving the way to the development of novel technological methods to control CF properties and morphology, especially to feasible hollow CF composites manufacture.

In this paper, the influence of carbon components in the composition of graphite paste on the electrical resistivity of a screen-printed carbon electrode is investigated. Graphite pastes with different contents of thermally expanded graphite (4.5–7.0 wt %), fine-grained graphite (0–6 wt %) and carbon black (0–12 wt %) are investigated. The creation of a polydisperse conducting system requires the application of carbon materials with different physical properties and particle sizes. This will lead to improvement in the screen-printing quality and reduce the resistivity of screen-printed carbon electrodes.

The structural and physical properties of onion-like carbon obtained in the process of partial oxidation of natural gas at different O-2/CH4 molar ratios were studied. It is established that when the molar oxygen/natural gas ratio increases from 0.650 to 0.750, the thermal stability limit of onion-like carbon increases from 520 to 620 degrees C. In an onion-like carbon sample obtained at a molar ratio of oxygen/natural gas of 0.750 in the temperature range from 680 to 750 degrees C, the presence of an oxidation- resistant carbon phase is observed. The interplanar spacing (d002) in the resulting onion-like carbon is 0.341 nm. Traces of trans-polyacetylene were detected by means of Raman spectroscopy at a Raman shift of 1164 cm(-1) in onion-like carbon. A paired peak was also detected at a Raman shift of 1480 cm(-1) as a result of the spectrum deconvolution. However, in the samples synthesized at temperatures higher than 1550 degrees C, no traces of trans-polyacetylene were detected. Heat treatment of the onion-like carbon in air at 320 degrees C leads to almost complete removal of these impurities. The ratio of peak intensities of ID/IG increases from 0.815 to 0.849 with an increase in the oxygen concentration in the raw mixture according to Raman spectroscopy data. The diffraction pattern of onion-like carbon corresponds to a defective graphitic structure, while its specific surface area varies from 80 to 100 m(2)/g. The production of onion-like carbon in the process of partial oxidation of natural gas can provide a high yield of the product at a low cost, while simultaneously producing synthesis gas of the necessary composition for "downstream" processes.

Высокая потребность в биосенсорах, с помощью которых можно количественно измерять концентрацию глюкозы в крови человека, приводит к поиску новых, недорогих и надёжных решений для удовлетворения растущего спроса.Основным компонентом таких биосенсоров является графитовый электрод, который наносят на подложку с помощью технологии трафаретной печати.Для трафаретной печати обычно используют графитовую пасту.Этовысокодисперсная коллоидная система, которая состоит из термопластичного полимера-диэлектрика, низкокипящего растворителя и электропроводящего компонента.Реология и физические свойства готовой графитовой пасты зависят в значительной мере от состава жидкой фазы, которая содержит раствор полимера и стабилизирующие компоненты

A simple method for applying superhydrophobic coatings based on carbon nano-onions obtained by a low-cost and technological synthesis method is proposed. The dependence of the hydrophobic properties of the coating on the application conditions, surface roughness and parameters of nanoobjects is analyzed.

Onion-like carbon (OLC) was investigated at high pressure (up to 48 GPa) in a shear diamond anvil cell (SDAC) equipped with in-situ Raman spectroscopy control. The OLC was obtained from natural gas by a highly productive and efficient partial oxidation method. Vast bulk modulus B-0 = 486 +/- 15 GPa and outstanding stability under high pressure were registered in the experiment. A phase transition was observed at 20 GPa under conditions of shear deformation. The transition is characterized by an appearance of a new Raman band at 1560 cm(-1) accompanied with disappearance of G band of OLC. We attribute these features to sp(2)-sp(3) transition in the carbon nanoclusters. It was found however that the concentric multi-shell onion-like structure remains intact after pressure release, which may witness that the outer shell of the OLC serves as a confinement and prevents structural collapse. X-ray photoelectron spectroscopy revealed however that the phase transition was not completely reversible because the OLC after pressure release showed the presence of sp(3)-hybridized carbon in significant amounts.

For the first time, a superhydrophobic coating based on onion-like carbon was synthesized by an economically feasible and scalable method was obtained. Two simple and easily reproducible methods of application are proposed. The possibility of using such coating to detect the composition and humidity of the air as well as its anti-icing properties are studied.

For the first time a superhydrophobic coating based on carbon nano-onions (multilayer fullerenes) synthesized through a cheap and technological method was obtained. Two simple and easily reproducible techniques of application were suggested. An opportunity of using the coating to control the composition and humidity of air was explored. Anti-icing properties were researched.

Abstract Onion-like carbon (OLC) particles were produced as a byproduct of thermal partial oxidation of methane under different O2/Natural Gas (NG) ratio. It was established that the particles have quasi-spherical morphology and concentric shell structure. The particles have an outer diameter of 20–60 nm while the inner cage is rather typical for onions and has a diameter below 1 nm. The concentric graphitic structure and spherical symmetry along with the absence of amorphous carbon were confirmed by transmission electron microscopy, electron diffraction, EDX spectroscopy and Raman investigation. Variation of O2/NG ratio was proved a powerful tool for controlling OLC particles yield and structure. The formation of single-core or multicore OLC can be controlled by thermal partial oxidation process.

It has been shown that the carbon soot produced as a byproduct of partial oxidation of methane consists of carbon nanoparticles of almost ideal spherical morphology and perfect concentric onion-like structure. The particles are unusually big for carbon onions and have outer diameter of 10-50 nm while the inner cage is rather typical for onions and has diameter below 1 nm. The concentric graphitic structure and spherical symmetry along with the absence of amorphous carbon are confirmed by transmission electron microscopy, electron diffraction, EDX spectroscopy and Raman investigation. The spherical particles get deposited on a wall of a partial oxidation reactor as loose particles embedded in a low density organic ovary, which can be detected by its luminescence or by cautious electron microscopy imaging. It is important that unlike literature reports on giant onions, the carbon deposit was dominated by these giant spheres. This process may be considered as a prototype for a production method for giant concentric shell carbon particle black.

The effect of saturation of methane with water vapor on soot formation at different saturation levels has been studied on a test facility of noncatalytic high-temperature partial oxidation of methane with syngas capacity of 8 Nm3/h. Relationship between the synthesis gas composition and the H2O/CH4 ratio has been revealed, as well as the qualitative and quantitative relations of the formation of soot agglomerates to the degree of saturation of pure methane or natural gas with water vapor. The structural features of the soot formed have been investigated by scanning and transmission electron microscopy and X-ray diffraction analysis.