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Information × Registration Number 0218U003788, 0116U007437 , R & D reports Title Photocatalytic properties of nanodisperse systems based on mesoporous iron and titanium oxides popup.stage_title Head Kotsiubynskyi Volodymyr Olegovych, Доктор фізико-математичних наук Registration Date 23-07-2018 Organization SHEE "Ргесаграthiаn NаtionаІ Vаsyl Stеfаnік Univetrsity" popup.description2 The reproducible methods of synthesis of nano-dispersed mesoporous systems of titanium dioxide (anatase, rutile and composite of anatase / rutile) based on their creation and testing were carried out by hydrolysis and hydrothermal treatment of precursors in the presence of NaCl or sulphate anions. As a result, non-linear change in the relative percentage of polymorphic phase anatase / brucite and increase the average size of crystallites material caused by increasing temperature annealing. Indirect optical transitions were detected for the brucite phase. Moreover, the influence of the degree of dispersion anatase and brucite on the width of the band gap is analyzed. A phenomenological model of the influence of Na + ions on the nucleation of phases of titanium dioxide has been constructed and the influence of structural parameters on the integral values of the widths of the forbidden zone of the obtained materials has been investigated. A comparative analysis of the influence of structural and morphological and electronic characteristics on photocatalytein has been carried out on the activity of the systems of dioxin-titanium obtained. It has been established that the presence of SO42- groups in the reaction medium leads to the formation of chelated bidentant complexes in the equatorial planes of the octahedra, which leads to the creation of conditions for the nucleation of the anatase phase. It was found that the maximum photocatalytic activity in the oxidation reaction of MB is possessed by a material with a maximum content of the BRUCITE phase, for which the band gap for direct allowed optical transitions is minimal (2.5 eV). This fact is due to the synergistic effect of such factors as the degree of crystallinity of the material, the specific surface area, the effect of size effects on the width of the band gap of the material components. Composite anatase / brookite materials exhibit the highest photocatalytic activity in the reactions by photodestruction of a formaldehyde solution. Probably is associated with an increase in the efficiency of separation of photogenerated electron-hole pairs for the case of the biphasic composition of the agglomerate particle of complex morphology Product Description popup.authors Бережницька Інна Дмитрівна Бойчук Андрій Михайлович Григорук Олександр Олесандрович Груб'як Андрій Богданович Колковський Павло Ігорович Коцюбинський Володимир Олегович Мокляк Марія Генадіївна Рачій Богдан Іванович popup.nrat_date 2020-04-02 Close