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[en] The hydrolytic stability of the Si-O-Ti bonds in titania nanostructures on the surface of silica materials of different genesis is analyzed. The mechanism of hydrolysis is considered and the decisive role of structural and chemical features of silicas in the stability of titania nanostructures on their surface is demonstrated.
[en] In connection with the development of nanotechnology in the last 15—20 years, the method of molecular layering (ML), created in the middle of the last century in the USSR, has attracted increasing attention. The features of structural-dimensional effects in the products obtained by new chemical nanotechnology and promising directions of their practical application in "core—nanoshell" compositions are considered in the review. In accordance with the synthetic capabilities of the ML method, the functional properties of the "core—nanoshell" type materials are affected by the "monolayer effect" and the substrate shielding effect, as well as the multicomponent nature of the system, and mutual structural coordination effect of the substrate and the build-up nanolayer. The review presents theoretical and experimental data on the application of the observed effects in the creation of shell pigments and fillers, modified sorbents, catalytic membrane reactors, nanodoped ceramic materials, polymers, quartz fibers with adjustable optical characteristics, electrets, etc.
[en] The surface topography of glass matrixes is investigated before and after oxide coatings caused by the molecular layering method. The conductance of synthesized nanolayers is investigated
[en] Properties of polytetrafluoroethylene films modified with mono- and two-component titanium-phosphorus oxide systems by alternating treatment of the polymeric substrate in a prescribed order with vapors of reagents from the series TiCl4, PCl3, and H2O were examined. It was found that the energy characteristics of the sample surface with two-component oxide systems P–Ti and Ti–P in comparison with polytetrafluoroethylene modified with only phosphorus or titanium oxide functional groups due to the increase in the polar component of the surface energy. Specific features of the effect of stabilization of the electret charge in modified polytetrafluoroethylene films. It was shown that the best electret properties are possessed by titanium-containing polytetrafluoroethylene films, including those with two-component titanium-phosphorus oxide additives. According to the results of a differential-thermal analysis, modified samples exhibit an increased thermo-oxidative stability manifested in that the onset temperature of the polymer decomposition increases by 40–50° and the loss of mass decreases by 17–23% as compared with an unmodified sample at 650°C.
[en] Effect of a simultaneous thermal treatment at 480°C and X-ray radiation (irradiation dose 10−3 C/kg (∼4 R) in a vacuum (residual pressure 10−3 Pa) on the structure and properties of titanium oxide nanocoatings of various thicknesses, synthesized by the molecular layering technology on the inner surface of glass bulbs of X-ray tubes, was examined. It was shown that the thermal and X-ray radiation treatments in a vacuum lead to a recrystallization of the titanium oxide layer and removal of oxygen atoms from its composition, which affects the electrical properties of the system.
Abstract—This paper presents a study of oxidative dehydrogenation of ethane (ODHE) on nanostructured single-component and multicomponent catalysts based on V5+, Mo5+, and Nb5+ oxides and produced on alumina by molecular layering. It has been shown that the molybdenum-containing catalysts exhibit higher activity for ODHE in both single-component and binary samples and ensure higher ethylene selectivity. We have demonstrated advantages of ODHE on membrane–catalyst systems in the form of asymmetric ceramic tubes, with catalysts placed inside of them. The membrane–catalyst systems produced by molecular layering offer considerably higher activity and selectivity in ODHE.