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Information × Registration Number 0214U002110, 0112U001659 , R & D reports Title Synthesis, structure and electrochemical properties of polyfunctional nanomaterials on iron oxides base popup.stage_title Head Budzulyak Ivan Mychaylovych, Registration Date 17-01-2014 Organization Centre of distance learning and knowledge control of Precerpathian national University named after V.Stefanyk popup.description2 Mesoporous g-Fe2O3 obtained by thermal decomposition of iron citrate hydrate xerogel. The influence of the precursors molar concentration in aqueous solution on the maghemite porosity, morphology and magnetic microstructure. The model of mesoporous g-Fe2O3 formation are presented. The results allowed to determine the conditions for obtaining magnetic nanomaterials ( mesoporous g-Fe2O3 ) with predetermined structural and morphological characteristics. Magnetic and optical properties of nanopowder maghemite depend on the material morphology and cluster organization so the possibilities of their purposefully modification during sol-gel synthesis are opened. The influence of the precursors molar concentration and calcination temperature on the material phase composition, crystalline and magnetic microstructure, surface condition and optical properties was studied. Nanodispersed powder formation involves two processes: association of particles during sintering and dispersion of material due to outgassing. Superparamagnetic state of the maghemite particles was detected and analyzed. The existence of the differences the iron atoms nearest neighbor for the central and near-surface layers of the maghemite particles of the material was proved. Obtained materials are heterogeneous - there are both areas that have properties of the bulk maghemite (band gap about 2.0 eV ) and regions where defects induce changes in the electronic structure while crystal ordering is kept. The reducing of band gap for superficial layers of g -Fe2O3 nanoparticles up to 1,43 - 1,70 eV was fixed. The A model of g -Fe2O3 nanoparticles formation is proposed. Product Description popup.authors Гарпуль О.З. Коцюбинський В.О. Левицька Б.І. Мандзюк В.І. Мокляк В.В. Морушко О.В. Рачій Б.І. Січка М.М. Федорів В.Д. Челядин В.Л. popup.nrat_date 2020-04-02 Close