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Information × Registration Number 0226U002856, (0125U001997) , R & D reports Title Physical processes of controlled synthesis of bioactive nanoparticles in reactive plasma popup.stage_title Розробка експериментального обладнання та методів діагностики, дослідження параметрів плазми та формування наночастинок у розряді постійного струму Head Lisovskyi Valerii O., Доктор фізико-математичних наук Registration Date 09-03-2026 Organization V.N. Karazin Kharkiv National University popup.description1 The project aims to develop physical principles for controlling the synthesis of nanoparticles with bioactive properties and methods for their retention in gas-discharge plasma. The main objectives of this research are as follows: - to develop and manufacture a gas-discharge chamber with vertically oriented electrodes, which can be powered by DC, RF or pulsed voltage; - to create a diagnostic complex consisting of a laser system for visualizing nanoparticles, a Langmuir probe, and an optical spectrometer; - to investigate spatial profiles of plasma parameters by probe and emission-spectral methods in various carbon-containing gases (C2H2, CH4, C6H6, CF4, and others) in DC, RF, and pulsed discharges in the pressure range from 1 to 100 Pa; - to study the spatial localization of the formation and retention of nanoparticles in these discharges using laser imaging; - to determine the influence of the voltage form from the power source (direct current, high-frequency, pulsed) on the parameters of the discharge plasma and, accordingly, on the formation and retention of nanoparticles; - to develop new methods for controlling the size of nanoparticles by changing the frequency and form of the voltage, pressure and type of gas; - to develop a new method for using nanoparticles as a means of diagnosing the structure of the potential distribution and electric fields; - to study the characteristics of nanoparticles obtained under different conditions using materials diagnostic methods (transmission and scanning electron microscopy, XRD, etc.); - to develop numerical models of the axial and radial structure of DC, pulsed and RF gas discharges under conditions of effective formation of nanoparticles; - to develop a method for the synthesis of combined polymer-metal nanoparticles containing metal atoms (in particular, silver) in the polymer matrix; - to study the antibacterial properties of combined polymer-metal nanoparticles. popup.description2 An experimental setup consisting of a gas discharge chamber, gas supply and exhaust systems, diagnostic tools for voltage, current, pressure, gas flow, Horiba iH320 optical spectrometer, cylindrical lens laser, Langmuir probe, and a mass spectrometer has been manufactured. The studies were conducted in CF4, CO2, C2H2, and mixtures of C2H2 with argon. The ignition curves of a direct current discharge were measured, and its glowing modes in various gases were determined. The effect of a significant reduction in the flow of secondary electrons emerging from the cathode surface under the influence of bombardment with positive ions was revealed if it is covered with monolayers of acetylene molecules. It was found that positive ions move in the cathode layer of the discharge in acetylene in a mode with constant mobility. This is possible only if the recharging of positive ions with acetylene molecules does not occur, that is, in the case of dominance of heavy ions. This was also confirmed by measurements of optical radiation from acetylene plasma carried out by the R&D team. It was shown that nanoparticles are usually formed and held in a potential well in the negative glow of the discharge. The shape of the cloud of nanoparticles, its temporal and spatial dynamics, as well as the conditions of its existence were studied. It was found that over time a flow of nanoparticles is formed from the cloud towards the anode. This phenomenon was explained using numerical PIC modeling. Using a transmission electron microscope and X-ray diffractometry (XRD), nanoparticles deposited from discharges in acetylene, argon, and their mixtures, both with a steel and silver cathode, were studied. Additionally, the antibacterial capabilities of the obtained nanoparticles were clarified. It was shown that polymeric nanoparticles, as well as pure silver ones, have practically no effect on bacteria. Nanoparticles formed in a discharge in oxygen with a silver cathode are AgxOy compounds and showe Product Description popup.authors Nadiia D. Kharchenko Yakovin Stanislav D. Ivan I. Okseniuk Dudin Stanislav V. Andrii H. Hakh Ihor E. Harkysha Anna V. Zykova Nina О. Yefymenko popup.nrat_date 2026-03-09 Close