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Information × Registration Number 0222U000619, 0120U000216 , R & D reports Title The effect of magnetic field and ultrasound on anion-exchange properties iron and cobalt-containing layered double hydroxides popup.stage_title Head Pashkevich Yurii G., Доктор фізико-математичних наук Registration Date 14-01-2022 Organization Galkin Donetsk Institute of Physics and Technology of the National Academy of Sciences of Ukraine popup.description2  Measurements of magnetization, magnetic susceptibility and magnetic heat capacity of layered double hydroxides (LDH) with different ratio of two and three valence cations with different anions in the temperature range 3 - 300 K and in the range of magnetic fields 0 - 5 Tesla were measured. The presence of magnetic anisotropy in cobalt-aluminum LDH has been established, which leads to the spatial orientation of nanoparticles in solutions. With the help of theoretical calculations, the mechanism of magnetic anisotropy due to the difference between the ionic radii of cobalt and aluminum and the specific distortion of hydroxide octahedra was revealed. It is shown that during the deposition of cobalt-containing LDH in a magnetic field due to magnetic anisotropy on the surface there is a compacted layer of LDH. A spectral method for estimating the ability of LDH to anion exchange has been proposed. The method is based on measurements of the absorption and inelastic light scattering spectra of hydrogen bonds depending on the relatie ratio of divalent and trivalent metals and the type of anion. It is established that the rate of anion exchange reaction (the number of released anions per unit time) increases linearly with increasing magnetic field in the exchange process of anion nitrate in cobalt aluminum LDH for carbonate anion. It was found that the number of released anions per unit time (ability to anion exchange) under the same starting conditions is significantly higher in LDH with a higher concentration of cobalt. Product Description popup.authors Babkin Roman Yurievich Gnezdilov Volodymyr P. Lukiienko Iryna N. Fedorchenko Oleksii Vitalievich Fertman Olena L popup.nrat_date 2022-03-09 Close