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Information × Registration Number 0210U000501, 0107U000405 , R & D reports Title Design and properties of light-sensitive systems based on guantum-dimensional metal-chalcogenide semiconductors popup.stage_title Head Kuchmii Stepan Yaroslavovich, Registration Date 18-02-2010 Organization L.V.Pysarzhevsky Institute of Physical Chemistry of National Academy of Science of Ukraine popup.description2 Objects of research - semiconductor nanoparticles and nanocomposites stabilized in colloidal solutions and organic polymeric matrixes, ultradispersed (mesoporous) titanium dioxide. The project purpose - development of physical and chemical principles of the design new photochemically- and optical-active systems based on quantum-sized semiconductors - oxides, sulphides and selenides of transition metals. Research methods - stationary and pulse photolysis, spectophotometery in UV and visible range of the spectrum, luminescent spectophotometery, Raman spectroscopy, X-ray diffraction, electronic microscopy, scanning microscopy, chromatographic and chemical analysis. Structural and spectral characteristics of CdxZn1-xS nanoparticles in aqueous colloidal solutions were studied. It was demonstrated that CdxZn1-xS nanoparticles have high capacity to a storage of an excess negative charge and the advanced stability to oxidative photocorrosion. Doping of CdxZn1-xS nanoparticles with metal cations results in an increase in the rate of photocorrosion attack. The colloids and nanodisperse powders CdxZn1-xS are effective photocatalysts of hydrogen evolution from water solutions of electron donors. A correlation between composition of nanoparticles CdxZn1-xS and their activity in the photoinitiation of polymerisation of acrylamide was found. Characteristics of the photocatalytic reduction of metylviologen by sodium sulfite with the participation of CdSe nanocrystals, particulary, the parallel process of metylviologen cation-radical reduction were found out. Possibility of control of the size of CdS nanoparticle using oxidative photocorrosion - for the size reduction and photocatalytic reduction of sulphur by ethanol in the presence of a cadmium acetate - for augmentation of the size of CdS nanoparticles was demonstrated. Possibility of photocatalytic formation of the spatially-ordered metal-chalcogenide nanostructures (nanospheres, nanotubes, nanorods) with the participation of ZnO nanocrystals was studied. The characteristics of photocatalytic synthesis of CdSe nanoparticles and the control of their size were found out. Spectral properties of CdS/CdSe nanoheterostructures produced by the photocatalytic CdSe deposition on the surface of CdS nanoparticles were studied. It was found that gold nanoparticles as large as 25-30 nanometers are produced in the course of the photocatalytic NaAuCl4 reduction by ethanol in the presence of ZnО nanoparticles. The photoproduced ZnО/Au nanoheterostructures can accumulate excessive charge when illuminated which testifies to high capacity of gold nanoparticles to charging. Titania powders with mesopores were found to be effective photocatalysts of molecular hydrogen evolution from alcohol-water mediums and organic vapors oxidation in the gas phase. Product Description popup.authors Гранчак Василь Михайлович Коржак Ганна Василівна Кучмій Степан Ярославович Раєвська Олександра Євгенівна Строюк Олександр Леонідович Швалагін Віталій Васильович popup.nrat_date 2020-04-02 Close