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Information × Registration Number 0223U003701, 0123U101228 , R & D reports Title Composite systems based on synthetic and natural dispersed and porous materials functionalized with organic and inorganic compounds popup.stage_title Head Hunko Volodymyr M., д.х.н. Registration Date 15-06-2023 Organization Chuiko Institute of Surface Chemistry of NAS of Ukraine popup.description2  Synthesized, a series of new Co4xFexOy/pyrogenic oxide nanocomposites was synthesized by thermal oxidation of metal salts adsorbed on individual and complex pyrogenic nanooxides. The influence of the carrier structure was analyzed with regard to the formation of deposited phases. The phase composition and average crystallite sizes determined by X-ray diffraction data show that the Co3O4 phase in the Co4xFexOy/pyrogenic oxide nanocomposites contains crystallites with a diameter of 25-37 nm, while iron oxide reflections are virtually unidentifiable. According to the CEM/EDX data, the formation of the deposited Co4xFexOy phase mainly occurs on the surface of the nanocarrier, which corresponds to the Al2O3 structural regions or the solid solution structures with Al-O-Ti, Al-O-Si, and Si-O-Ti bridges. When the Co4xFexOy phase is applied to the carrier, the specific surface area of the composites slightly decreases. Incremental pore size distribution functions mainly show the mesoporosity of nanocomposites, the volume of mesopores increases significantly compared to the original pyrogenic oxides. According to LCS data, small aggregates with several nanoparticles of 100 nm in size, large aggregates up to ~1 μm, and agglomerates up to 5.5 μm are observed for aqueous dispersions of synthesized nanocomposites. There is a general tendency to increase the size of aggregates due to the modification of nanocarriers with deposited Co4xFexOy. The magnetic properties of Co4xFexOy/pyrogenic oxide nanocomposites according to the magnetization curves are characterized by a hysteresis loop with superparamagnetic behavior for Co4xFexOy/SA96 and Co4xFexOy/A2O3 (Hc = 43.05 Oe and 56.5 Oe, respectively) and a mixture of superparamagnetic and ferromagnetic for Co4xFexOy/SiO2 nanocomposites and Co4xFexOy/AST1 (Hc = 386.5 Oe and 117.8 Oe, respectively). Product Description popup.authors Andryiko Lyudmyla S. Golovkova Luydmila P. Guzenko Nataliya V. Kazakova Olga O. Matkovsky Oleksandr K. Nychyporuk Yuriy M. Nosach Liudmyla Viktorivna Paentko Victoriya V. Pachlov Evgen M. popup.nrat_date 2023-06-15 Close