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Information × Registration Number 0218U001876, 0115U004201 , R & D reports Title Creatiоn of the new functional systems based on heterogeneous ensembles of metaloxide nanoparticles. popup.stage_title Head Gorban Oksana Oleksandrivna, Кандидат хімічних наук Registration Date 18-12-2018 Organization Donetsk Institute of Physics @ Engineering named after O.O.Galkin NAS of Ukraine popup.description2 The objects of investigation are the oxide nanopowders of the composition ZnO, ZrO2-ZnO Ag2O (Ag), their structure and surface state, phase stability, optical properties, heteroencemics and photocatalytic activity. The aim of the work is to optimize the chemical compositions and methods of obtaining of heterogeneous ensembles of metal oxide particles based on a detailed analysis of the characteristics of individual components and the ensemble as a whole, to identify the factors leading to maximum effects in the properties of a complex material. X-ray analysis, X-ray phase analysis, EPR, UV-Visible spectroscopy, liquid chromatography, equipment for UV degradation of phenol were used. A methodology for the synthesis of multicomponent composite systems based on ZnO-ZrO2 / Ag2O (Ag) has been developed. The effects of the synthesis mode (nature of precursors, type and amount of doping impurity, temperature) on the structure of the composite material, which was formed, were studied using X-ray diffraction, EPR, and UV-visible spectroscopy. The features of the formation of Ag-containing ZnO-0.1 mol ZrO2 depending on the type of defects in the zinc oxide matrix is considered. It was revealed that a metal / oxide composite structure is formed only for a system with defects in the anion sublattice. For systems that have defects in the cation sublattice, the solubility of silver in the zinc oxide matrix with the formation of shallow acceptor levels is observed. It was shown that the appearance of shallow acceptor levels in the zinc oxide matrix leads to inhibition of the photocatalytic activity of the material. Phase diagrams ZnO-x mol% ZrO2, ZnO-x mol % ZrO2-Ag2O, obtained from various precursors in the range of concentrations of ZnO- 10-60 mol % and processing temperatures of 500-1000°С is obtained. It is shown that the type of precursor affects the solubility of zinc oxide in the zirconia matrix and the course of the processes of formation and decomposition of solid solutions of this composition. The questions of the relationship between the structure of the composite material and its optical properties are considered. The scientific significance lies in identifying factors that influence the characteristics, behaviour and processes of the formation of complex ZnO-ZrO2 / Ag2O (Ag) systems under conditions of concentration and temperature. Practical significance: technological procedures for the synthesis of composite heterogeneous systems based on zinc oxide and zirconia, including those doped with silver compounds, have been developed, which makes it possible to control the catalytic activity of nanoparticles during their preparation, as well as their optical properties. Product Description popup.authors Ахкозов Л.А. Горбань C.В. Даніленко І.А. Лакуста М.В. Синякіна С.А. Шило А.В. popup.nrat_date 2020-04-02 Close