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Information × Registration Number 0218U000736, 0115U002961 , R & D reports Title The development of physico-chemical principles of creating nanoscale materials based on 2D-structures and organic conducting polymers popup.stage_title Head Koschechko Vyacheslav Grygorovych; Pokhodenko Vitaliy Dmytrovych, Доктор хімічних наук Registration Date 12-02-2018 Organization L.V.Pysarzhevsky Institute of Physical Chemistry of National Academy of Science of Ukraine popup.description2 For the first time it is mechanochemically synthesized, graphene, doped with nitrogen and fluorine, with a content of 3.1%, which allows to obtain their highly concentrated dispersions in water and organic solvents with a lateral size of particles of graphene to 1-2 microns and a thickness of ~ 0.75 nm. It was established that nitrogen atoms in the structure of graphene are in the pyridine, pyrrole and amino groups, and the fluorine atoms are bound to carbon atoms, mainly by half-ionic bonds. It was established that mechanochemically obtained graphene oxide (GO | mc) consists of low molecular weight "fragments" and sufficiently large graphene sheets. It was found that the presence of a low molecular weight fraction causes the formation of GO | mc dispersions without the use of ultrasound. It was shown that GO | mc demonstrates photoluminescence in the visible part of the spectrum, the main contribution of which is fraction of "fragments". It was established that the application of the mechanochemical approach to the synthesis of inorganic perovskite CsPbBr3 leads to the formation of a highly crystalline nanostructured product with nanoparticles of 10-50 nm in size. It was found that the treatment of CsPbBr3 with dimethylformamide promotes to the cleavage of its nanoparticles into individual nanosheets, which leads to an increase of the band gap and Urbach energy, as well as to the hypochromic shift of the photoluminescence band of this perovskite. According to the data of non-stationary photoluminescence, the resulting material is characterized by a small number of defects. It was obtained the material (N, P-doped, reduced OG with nanosized carbide of molybdenum) by carbonization of a hybrid composite based on poly-5-aminoindole, 12-phosphoramolybdic acid and graphene oxide (OG), which is an effective electrocatalysatian of the hydrogen evolution reaction (RHE) from water , whose characteristics (over-voltage ~ 135 mV at a current density of 5 mA/cm2) significantly exceed the known analogues. It was discovered that the method of obtaining carbon-based Co-N-C electrocatalysts RHE based on polyaminoindole essentially affects on their electro-catalytic characteristics, and one of the reasons for the increased activity of these electrocatalysts in RHE may be the formation of Co9S8 particles by the use of ammonium persulfate in the reaction mixture. Product Description popup.authors Козаренко Ольга Андріївна Конощук Наталія Володимирівна Кошечко В'ячеслав Григорович КурисьЯрослав Іванович Посудієвський Олег Юлійович Походенко Віталій Дмитрович popup.nrat_date 2020-04-02 Close