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Information × Registration Number 0211U001217, 0110U003330 , R & D reports Title Nanocomposites ТіО2<Fe> as active cathode material in the energy generation devices: Mossbauer study popup.stage_title Head Мокliaк Volodymyr Volodymyrovych, Кандидат фізико-математичних наук Registration Date 25-01-2011 Organization Institute of Metal Physic G.V.Kurdyumov NAS of the Ukraine popup.description2 The complex of researches aimed at developing the methods of obtaining of nanodispersed titanium oxides doped with iron ions is carried out. The effect of the use of 5 mass. % Na2SO4 (or Na2CO3) salt solution as additional precursors in a reaction mixture on the olational processes of TiO2 anatase modifications condensation formation is investigated. Intercalation of lithium ions in TiO2/Fe nanosystem leads to change of trivalent iron ions to two-valent state, concentration of which is directly proportional to the size of "guest" loading. Intercalation effects experienced only the iron ions, which are located in material super paramagnetic particles. Isothermal annealing of TiO2/Fe nanocomposite in the temperature range of 200-360 C does not change the magnetic microstructure and it is accompanied by material dehydration. Mossbauer researches at temperatures of 293 K and 88 K for the group of TiO2/Fe materials did not reveal magnetically ordered iron phases. In the samples Fe3+ ions are presented in octahedral surrounding and they are the part of the X-ray-amorphous compound of gamma-FeOOH, that indicates the localization of about 60% Fe3+ ions in the highdefected subsurface layer of composite nanoparticles and their interaction with the chemisorbed on the surface hydroxyl groups. The model of nanocomposite TiO2 (anatase) / Fe formation in the process of joint hydrolysis is suggested. There is as isomorphic substitution of titanium by iron in the crystal matrix nodes, and localization of iron ions on the surface of crystalline phase germs with formation of chemical bonds with O-2 ions, which are in the equatorial plane of the TiO6 octahedra. Increasing of isomorphic substitution of titanium ions by iron ions in the lattice of anatase is reducing the efficiency of using such material as the basis of cathode material for lithium power sources. Product Description popup.authors Коцюбинський Володимир Олегович Мокляк Володимир Володимирович Челядин Володимир Любомирович popup.nrat_date 2020-04-02 Close