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Information × Registration Number 0219U000817, 0116U000302 , R & D reports Title Establishment of regularities of interaction in systems Germanium - metal sulfide (selenide, oxide) with formation of volatile compounds for formation of thin-film coatings popup.stage_title Head Zinchenko Viktor Fedosiyovych, Registration Date 27-02-2019 Organization A.V. Bogatsky, Physico-Chemical Institute of the National Academy of Sciences of Ukraine popup.description2 The problem of detection and determination of chemical forms of Germanium in various objects is considered. It is noted that this area of analytical chemistry (unlike many other elements) of Germanium is poorly developed. It is shown that while detecting and determining the forms of Germanium in the environment, the most effective ones are combined methods, combinations of the procedure of separation and concentration of forms with a highly sensitive determination using physical methods of analysis. Quantitative determination of Germanium forms in inorganic materials is carried out mainly by the method of redoxmetry and selective extraction of the form by specific solvents. The difficulty of quantitative analysis associated with the variety of forms of Germanium and crystalline modifications, as well as ways to verify the definition is noted. Chemical analysis of samples of germanium-containing materials, including GeO2, GeO and in the residue after thermal evaporation in vacuum of a CVD - composite of ZnO-Ge composition was carried out. In the case of GeO2, the Ge content corresponds to stoichiometry, while the content of Germanium in GeO indicates the presence of impurities GeO2. The content of Zn and Ge in the residue corresponds to the presence of compounds Zn2GeO4, ZnO and Ge elemental. Thermodynamic calculations have estimated the temperatures at which the total pressure of the gaseous reaction products is ~1Pa (10-5 bar). The indicated value is significantly (by hundreds of °C) lower compared to the initial components (the metal compound and Germanium). The thin-film coatings obtained by the condensation of the vapors of these composites possess optical and operational parameters that exceed similar values for the initial components and are transparent in an IR spectral range. The nanostructural character of the coatings have been established due to a significant supersaturation of vapor during reverse exchange reactions on the substrate surface. The behavior during thermal evaporation of Germanium monoxide as a natural nanocomposite, which has a very low conventional temperature (350°C), is considered, which results in the formation of coatings with low mechanical durability. The use of a Boron oxide dopant stabilizes the valence state of Ge (II) and contributes to a significant improvement in the properties of the coatings obtained from the material. The kinetics of thermal evaporation in vacuum of chalcospinel-Germanium composites and condensation of coatings was investigated and the relationship between the process rate and the strength of metal-chalcogen and Germanium-chalcogen bonds was found. It has been established that the coatings obtained from composites with the lowest volatility (Europium chalcospinel - Germanium) have the highest mechanical strength values. Product Description popup.authors Єрьомін О.Г. Іллюшко Н.О. Антонович В.П. Вольчак Г.В. Городнюк В.П. Магунов І.Р. Садковська Л.В. Стамікосто О.В. Стоянова І.В. Чівірева Н.О. Чистов О.С. popup.nrat_date 2020-04-02 Close