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Information × Registration Number 0222U005324, 0121U111831 , R & D reports Title Engineering of media based on oxide nanomaterials for electrical energy storage systems popup.stage_title Head Shylo Artem V., Кандидат фізико-математичних наук Registration Date 27-12-2022 Organization Galkin Donetsk Institute of Physics and Technology of the National Academy of Sciences of Ukraine popup.description2 Aim of work - determine the characteristics of electrokinetic processes that occurs in nanopowder systems based on zirconia under the action of an electric field, to establish physical and chemical conditions for accumulation of electrical energy in structures based on nanostructured zirconia. Objects of study - oxide nanopowders of composition ZrO2+3%Y2O3. Research methods – electrochemical impedance spectroscopy; distribution of relaxation times analysis; 1H nuclear magnetic resonance (NMR); thermogravimetric analysis; voltammetry. The results of the study – the presence of three relaxation processes in the particle–adsorbed layer of water system was established by NMR method, which indicates different mobility of water molecules in adsorbed layer and corresponds to its components – Stern layer, diffuse layer, free water layer. Increasing hydration of nanopowder to maximum leads to filling of adsorbed layer on particles, which leads to increase in electrical capacity of Stern layer by 13 times and free water layer by 15 times. It was found that ZrO2–3%Y2O3 nanopowders are able to accumulate an electric charge when constant electric field is applied. The effect depends on characteristics of powder and humidity of environment. The maximum level of voltage was observed for the powder with annealing temperature of 400°C and was 1.72V. It was established that the increase in capacity and dielectric constant of samples is related to evolution and geometry of water layers on surface of nanoparticles and Maxwell–Wagner effect. The contribution of this type of polarization to total polarization of heterogeneous system increases with an increase in the electrical contrast of its components, which is determined by number and type of active centers, number of water layers on nanoparticles surface. The main characteristics of electrokinetic processes occurring in hydrated zirconia nanopowders under the action of electric field were determined. Product Description popup.authors Kredentser Serhii Viktorovych popup.nrat_date 2022-12-27 Close