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Information × Registration Number 0213U001338, 0111U000113 , R & D reports Title Bases of creation of nanomaterials with phase transition physical and chemical semiconductor-metal for photonic crystals popup.stage_title Head Chernenko Ivan Mikhajlovich, Registration Date 18-02-2013 Organization State higher educational entity "Ukrainian State University of Chemical Technology" popup.description2 The object of research are the vanadium oxide systems, methods of description of nanoparticles self-organization. The purpose of work is the research of properties of the vanadium oxide systems and creation of computing methods for the description of nanoparticles self-organization in colloid solutions. Research methods: thermodynamics computing methods, imitation modeling, physical and chemical experimental. It is set as a result of modeling of process of tetravanadat (IV) ammonium synthesis that in the actual conditions the near-equilibrium state is achieved, and the separation of the indicated compound can transform its composition. It was found that the product of the reaction of vanadyl oxalate complex with ammonium hydroxide is nanodispersed (NH4)2V4O9 which is a precursor for the synthesis of vanadium dioxide with a semiconductor-metal phase transition. When just obtained in alkaline medium (NH4)2V4O9 is rapidly oxidized by atmospheric oxygen according to the first order kinetic. At heat treatment of vanadium containing compounds in presence of ammonium oxalate in the atmosphere of argon the reduction of vanadium (IV) to the lower degree of oxidization with formation of vanadium trioxide takes place. Vanadium trioxide also has a phase semiconductor-metal transition. As a result of the research of regularities of the self-ordering systems formation by imitation modeling methods it was determined that packing quality improves with the increase of concentration of particles and the reduction of their diameter deviation from the average value. The range of application: К 73.10.1research and development in the field of natural sciences, DG 24.66.0 production of semiconductor materials. Product Description popup.authors Євтушенко Олександр Васильович Бубель Тетяна Олександрівна Гиренко Альона Олександрівна Каюн Ігор Георгійович Мисов Олег Петрович Савченко Марія Олегівна popup.nrat_date 2020-04-02 Close