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Information × Registration Number 0225U002454, (0124U001654) , R & D reports Title Microwave properties of nanocomposites based on substituted hexaferrites in the high-frequency range of electromagnetic radiation popup.stage_title Удосконалення методів та виготовлення експериментальних зразків, дослідження їх магнітних та електричних властивостей. Head Yakovenko Olena S., Кандидат фізико-математичних наук Registration Date 12-03-2025 Organization Taras Shevchenko National University of Kyiv popup.description1 The aim of this project is to develop the physical basis for the creation of new multicomponent composite materials (CM) of the polymer/nanocarbon/ferrite type using particles of nanocarbon of various morphologies and particles of magneto-dielectrics as nanofillers of polymer matrix (hexaferrite BaFe12O19 and substituted hexagonal M-type ferrites Ba(Fe(1-x)DIx)12O19, where DI3+, x>0.1, and substituted copper ferrites with a spinel structure) for effective control of the electromagnetic characteristics of CM when interacting with the electromagnetic radiation (EMR) in the short-wave part of the electromagnetic spectrum and on the basis of detailed theoretical and experimental research establishing the relationship between methods of obtaining, structure, phase composition of the carbon component and ferrite nanoparticles, the nature of their spatial distribution in the CM and electrodynamic and magnetic characteristics. popup.description2 Ni- and Co-substituted copper ferrites Cu1-xNixFe2O4, Cu1-xCoxFe2O4 (x=0.0; 0.2; 0.4; 0.6; 0.8; 1.0) were synthesized by the sol-gel autocombustion method. The crystallite sizes were determined by X-ray analysis using Williamson-Hall plots. The single-phase nature of the synthesized ferrites and their classification in the Fd3m space group was confirmed by modeling the X-ray spectrum using the Rietveld method. The magnetic properties of the fabricated ferrites were investigated and, analyzing the average values of the saturation magnetization and coercive force, it was established that the synthesized samples are soft magnetic materials, the degree of "hardness" of which increases from CuFe2O4 to CoFe2O4. The decrease in the magnetization of the studied samples by 10–30% compared to the bulk properties is explained by the presence of a magnetically inactive “dead” layer on the surface of the nanoparticles. New nanocarbon/polymer composite materials with the addition of magnetic dielectrics (hexaferrite BaFe12O19 and substituted hexagonal ferrites of the M-type Ba(Fe(1-x)DIx)12O19, where DI3+, x>0.1) and substituted copper ferrites with a spinel structure were produced by the liquid-phase method with preliminary ultrasonic dispersion of fillers, and their electrical properties were investigated depending on the types of nanocarbon and magnetic fillers and their content, which will allow developing technological principles for the manufacture of new nanocarbon/polymer/ferrite composites with adjustable absorbing properties by combining fillers of given types in a certain percentage, taking into account the spatial distribution of fillers in the composite, and the scientific foundations for regulating the electrical and electromagnetic properties of such composites.  Product Description popup.authors Bandura Khrysyna V. Dubyk Kateryna V. Mazurenko Yuliia S. Shpylka Denys O. popup.nrat_date 2025-03-12 Close