The electrochemical behavior of three alloys of different composition in the system Al65Cu25Fe10 –хCrх is studied by the potentiodynamic method in alkaline and neutral media as a function of the number of quasi-crystalline phases. The chromium-containing alloys characterized by the presence of the quasi-crystalline (decagonal and icosahedral) components demonstrate the highest stability. It is shown that as the solution pH increases, the corrosion stability of samples decreases.

The electrochemical behavior of five alloys of variable compositions in the Al65Cu25Fe10–хCr х system in dependence on the number of QC phases in acidic and alkaline media has been investigated by the potentiodynamic method. It has been established that the samples’ corrosion stabilities increase along with the increase of the solution pH. Higher stability was manifested by alloys with a predominant quasi-crystalline (dexagonal and icosahedral) structural component.

Quasicrystalline Al–Cu–Fe–Cr alloys have been prepared by mechanical activation. The morphology of powder particles has been investigated after thermomechanical processing under various conditions. We have identified the sequence of phase transformations in the quaternary alloys in the stability region of quasicrystalline phases and optimized conditions for obtaining a maximum fraction of a decagonal state in powder materials.

Phase equilibria in the Al–Cu–Fe system alloyed with 5% Cr were studied. Based on the data of X-ray powder diffraction analysis, electron microscopy, and differential thermal analysis, the effect of temperature on i ⇔ d phase transitions in alloys Al 65 Cu 25 Fe 5 Cr 5 and Al 70 Cu 20 Fe 5 Cr 5 . In the Al–Cu–Fe–Cr system, multiphase structures were detected; these structures are mixtures of quasi-crystalline and approximant phases, the contents and morphologies of which depend on the composition of the initial mixture and the crystallization rate.

Nanocrystalline antimony-doped ([Sb]/([Sb] + [Sn]) = 0–2 at %) SnO 2 powders have been synthesized by coprecipitation from solution. The composition, crystal structure, and microstructural parameters of the powders, as well as the antimony distribution in them, have been studied by laser mass spectrometry, X-ray diffraction, low-temperature nitrogen adsorption measurements, and IR spectroscopy. The reaction of the synthesized materials with oxygen has been studied in situ by electrical conductance measurements. Oxygen chemisorption on the surface of unmodified SnO 2 leads to predominant formation of the molecular species O 2(ads) - . Increasing the Sb concentration in the SnO 2 ‹Sb› samples increases the fraction of the monatomic species O 2(ads) - , which can be explained in terms of a combination of crystal-chemical and electronic factors.

The phase transformations in Al-Cu-Fe cast alloys in the region of existence of the ico-phase are characterized via X-ray diffraction, X-ray fluorescence, and scanning electron microscopy. It is established that the production of multiphase structures consists of a mixture of quasi-crystalline and approximant phases, the amount and morphology of which depend on both the shield composition and crystallization mode. The optimum annealing time for the cast samples at 800°C has been determined, resulting in complete transformation of approximant crystalline phases into a quasi-crystalline ico-phase.

A quasicrystalline compound of composition Al64Cu24Fe12 has been prepared through mechanical activation. We have studied the morphology of powder particles after heat treatment under various conditions, identified the sequence of phase transformations in Al-Cu-Fe alloys in the stability region of the ico-phase, and optimized conditions for the preparation of powders containing the maximum possible percentage of the quasicrystalline phase.

Crystallization processes in the aluminum-rich region of the ternary Al-Cr-Zr system were studied via the complex of the methods of physical and chemical analysis. It was found that in the equilibrium crystallization of these alloys along the Cr: Zr = 14: 5 section, aluminum and the CrAl7 intermetallic compound are crystallized, whereas under non-equilibrium conditions at quenching rates of 106 degree s−1, ZrAl3 phase and aluminum-based supersaturated solid solution are formed.

The powders of nanocrystalline tin dioxide were prepared by two different methods: conventional hydrolysis of SnCl4 in aqueous solution and novel cryosol technique. The microstructure, composition, and electrical properties of the samples were investigated. The sintered pellets obtained by means of the cryosol method are characterized by significantly higher values of electrical resistance as compared to those prepared by conventional technique. A significant effect of the microstructure on the sensing properties of nanocrystalline SnO2 has been found. The sensitivity to H2S of the samples synthesized by cryosol method was shown to be higher than that of the samples obtained by traditional precipitation.

A novel approach has been proposed for producing model catalysts via oxidation of molybdenum- platinum alloys. The effect of alloy composition on the structure and morphology of the oxidation products has been studied, and heat-treatment conditions have been optimized to achieve a uniform distribution of fine platinum particles in the resulting molybdenum oxide.

A novel approach has been proposed for producing platinum-containing catalysts via oxidation of molybdenum-platinum powders. The effect of alloy composition on the structure and morphology of the oxidation products has been studied by a variety of physicochemical methods, and heat-treatment conditions have been optimized to achieve a uniform distribution of platinum nanoparticles in the resulting molybdenum oxide. Selective oxidation has been shown to be a viable approach to producing platinum-transition metal oxide catalytic systems.