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The photocatalytic activity of heterostructural α-Bi2O3/Bi compositions obtained by low-temperature pyrolysis of bismuth complexes with sorbite has been investigated. The efficiency of catalysts has been estimated based on the decomposition rate of methylene blue under illumination by visible light. The obtained catalysts are characterized by different contents of metallic Bi and different degrees of imperfection of the α-Bi2O3 lattice, which was obtained by changing the amount of sorbite in the composition of the precursor organomineral bismuth complex and varying the synthesis temperature. It is established that isothermal annealing of the α-Bi2O3/Bi compositions in air in the range of 400–600°C leads to relaxation of defects and an increase in the α-Bi2O3 lattice volume. An increase in the annealing temperature to 550°C is accompanied by a rise in the α-Bi2O3/Bi catalytic activity. However, the heterostructure degrades at higher temperatures as a result of metallic bismuth oxidation, while the catalytic activity decreases.

The results of a cross-correlation analysis of the relationship between the process conditions for obtaining CoNiFeSiB amorphous alloys, their physical and chemical properties and structure are presented. The alloys are obtained by single-roll rapid quenching on a copper wheel at frequencies from 30 to 60 Hz, which corresponds to linear velocities from 22 to 38 m/s, a chamber pressure from 0.05 to 0.6 atm, and a pressure in the crucible from 0.4 to 0.6 atm. Elemental analysis is carried out; the atomic and surface structures, phase-transition parameters upon heating, and the corrosion properties are investigated. Correlations between the structural-ordering parameters and physical and chemical properties are determined. Regression models of the dependence between the structural characteristics, physical and chemical properties, and process conditions of production are formulated. A regression model for the dependence of the average cluster area in the atomic image on the specific energy of structural changes is proposed. The concentrations of nickel, silicon, and boron in cobalt-based alloys are found to play an important role in determining the structural characteristics and properties of the alloys.

FeCrWMoC metallic glass (MG) is synthesized in the form of coatings by electric spark treatment in grain media consisting of individual components. It is demonstrated that the amorphous phase fraction in the composition of the coatings increases with the time of the granule treatment increasing to 100–150 min. The proposed approach offers the potential for the one-stage synthesis of MG in the form of coatings in the automatic mode.

The synthesis of nanotubes and faceted nanocrystals of titanium dioxide doped with alkali metals cations has been performed. It has been established that TiO2 nanotubes with lengths of up to 100 nm and thicknesses of 50–500 nm obtained by solvothermal synthesis have an anatase structure in the direction of crystal growth. Faceted TiO2 particles with sizes of 80–150 nm doped with Na and K cations (2–7 at % calculated to a yield of TiO2 yield) preserve the anatase structure, whereas doping with Li induces the formation of a mixture of anatase and rutile. An analysis of the diffuse reflectance spectra showed that dopants had an insignificant effect on optic properties of TiO2 nanoparticles. The high activity of these catalysts is explained by a decrease in the rate of recombination of charge carriers, rather than by the increase of their photo-generation yield.

Titanium oxide particles are produced using electric-discharge dispersion of titanium in aqueous solution of hydrogen peroxide. Electron vacuum microscopy, X-ray diffraction, and diffuse reflection spectroscopy are used to study the morphology, composition, and optical characteristics of the erosion particles. It has been demonstrated that the particles consist of titanium and titanium oxides with different valences. The edge of the optical absorption is located in the UV spectral range. The band gap is 3.35 eV for indirect transitions and 3.87 eV for direct allowed transitions. The band gap decreases due to the relatively long heating in air at a temperature of 480–550°C, so that powder oxide compositions can be obtained, the optical characteristics of which are similar to optical characteristics of anatase. The erosion products are completely oxidized to rutile after annealing in air at a temperature of 1000°C.

Carbonaceous matter (CM) in shales of some deposits and occurrences of the Russian Far East has been studied by scanning and transmission electron microscopy, Raman spectroscopy, and X-ray phase and differential thermal analyses. It was shown that the carbonaceous matter in the high-temperature shales (amphibolite facies) of the Soyuznoe deposit is represented by holocrystalline graphite, while the low-temperature (greenschist facies) shales of the Sutyr and Kimkan sequences contain mainly nanocrystalline graphite. It was substantiated for natural objects that platinum is assimilated by graphite at high temperatures. This should be taken into account in planning the prospecting works, as well as in developing a technique for enrichment of carbonaceous ore, because high-temperature carbonaceous shales with holocrystalline graphite are promising for Pt, unlike their low-temperature analogues with nanocrystalline graphite.

Coatings containing Ti-Al intermetallics are fabricated by the electrospark deposition of titanium on aluminum and aluminum on titanium. The microstructure and composition of the grown coatings is studied by scanning electron microscopy, X-ray diffraction, and S-ray microanalysis. It is found that the surface layer formed in argon mostly contains the α-TiAl3 intermetallic independent of the duration and frequency of discharge pulses. The γ-TiAl and α2-Ti3Al phases can be obtained by aluminum deposition on titanium followed by the subsequent deposition of a second titanium layer. Aluminum oxide and titanium nitride are additionally formed during the deposition of electrospark coatings in air.

The surface of copper cathode foils with thicknesses up to 50 μm has been studied after a single discharge current pulse with an amplitude of up to 60 A and a pulse duration within 50–1300 μs in air at atmospheric pressure. It is established that the foil surface upon discharge is covered by copper nanoparticles with diameters above 30 nm, which form an ordered array with a cellular structure and dimensions of up to several hundred nanometers. A possible mechanism of this self-ordered structure formation is qualitatively described.

Experimental evidence is presented that the growth of tungsten whiskers during CO reduction of NiWO4 follows the vapor-liquid-solid mechanism. A liquid phase appears at 940°C owing to the melting of NiWO4-Na2WO4 eutectic regions which seem to result from the segregation of sodium impurities present in the reagents used. The presence of the liquid phase ensures comparable rates of Ni and W liberation from the crystal lattice of nickel tungstate, leading to the formation of α-W + NiW two-phase regions. The directional growth of tungsten whiskers during further CO reduction of the tungstate melt is associated with W deposition on the growth surfaces of α-W single crystals in the two-phase regions.

The microstructure and phase composition of a copper foil subjected to single low-voltage discharges of different duration and power have been studied. It was found that the grain size decreases from 200 μm to 10 nm with approaching the center of the discharge-affected zone. The electron-microscopic examinations showed that the compounds formed by electrode materials and oxygen were regularly distributed depending on the distance from the center of the discharge-affected region.