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Information × Registration Number 0220U101549, 0119U002037 , R & D reports Title Influence of lanthanides coordination environment and size factors on the properties of lanthanide fluorophores and hybrid systems based on them popup.stage_title Head Dotsenko Volodymyr P., Доктор хімічних наук Registration Date 12-02-2020 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2 In order to develop approaches to the directed production of materials with high emission characteristics, the influence of structural features and dimensional factors on the luminescent properties of coordination and inorganic lanthanide-containing compounds is analyzed. Analysis of the action of a number of factors (type of surface-active substance (SAS), phase transformations, degree of structural disorder) on the processes of transformation of excitation energy in complexes of Eu (III), Tb (III) with certain drugs and doped with Eu (II, III) ions Al2O3 was studied by dynamic light scattering, laser diffraction, electron microscopy, and luminescent spectroscopy. It was found that the luminescence intensities of the Eu (III), Tb (III) complexes with the addition of SAS increase from one and a half to 19 times. It was shown that this effect is not directly related to the particle size of the complexes, other factors, such as the displacement of water molecules from the internal coordination sphere of the complex and the increase in complex rigidity in coordination with SAS, the transfer of excitation energy from SAS to lanthanide ions are dominant. Nanoscale (10-70 nm) Al2O3 activated by Eu2+/3+ ions was obtained by combustion. It was shown that in the final synthesis products (δ *, δ- Al2O3), part of europium stabilizes in the +2 oxidation state and causes a broad luminescence band with a maximum at ~ 400 nm and a decay time of τ = ~ 405 ns. Annealing at 1200°С leads to the formation of a stable α-modification and to a significant decrease in the degree of structural disorder of Al2O3. With the conversion to α-Al2O3, changes also occur in the morphology of particles: an increase in the size of crystallites and the formation of vermicular microstructures. It was concluded that nanosized Al2O3:Eu2+/3+ synthesized by gas-phase combustion method is a promising precursor for the production of luminescent optoelectronic ceramics.  Product Description popup.authors Yegorova Alla V. Efryushina Ninel P. Antonovich Valerij P. Berezovskaya Irina V. Doha Pavlo G. Dotsenko Volodymir P. Korovin Oleksandr Yu. Pochinoc Elvira V. Rusakova Nataliia V. Semenishyn Mykola M. Skrypynets Yuliia V. Smola Serhii S. Fadieiev Yevhen M. Khomenko Olena V. popup.nrat_date 2020-04-02 Close