Registration Number
0222U000231,
0119U100025
, R & D reports
Title
Polyoxometalates, orthovanadates and oxyorthosilicates of transition metals and lanthanides for creation of new materials
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Head
Rozantsev Georgiy M., Доктор хімічних наук
Registration Date
05-01-2022
Organization
Vasyl' Stus Donetsk National University
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The formation of Ho(III)-containing polyoxotungstates in acidified to different acidity Z = ν(H+)/ν(WO42–) = 0.80, 1.17, 1.29, and 1.50 solutions of the system Na2WO4 – HNO3 – Ho(NO3)3 – H2O was studied. The conditions for the synthesis of Na9[Но(W5O18)2]·23H2O, Na2Ho2[Нo2(H2O)10W22O72(OH)2]·46H2O, Ho10[W12O40(OH)2]3·54H2O were established. Synthesis and X-ray diffraction analysis of crystalline phases isolated from solutions of systems A+–Y3+–WO42––H+–H2O (A+ = K+, NH4+) and M2+–Y3+–WO42––H+–H2O (M2+ = Mg2+, Zn2+) at acidity Z = 0,80 were performed. Synthesized and characterized by FTIR spectroscopy, SEM and single crystal X-ray analysis Na2(NH4)8[W12O40(OH)2]∙12H2O and К10[W12O40(OH)2]∙13H2O, the formation of which occurs as a result of hydrolytic conversion of [Y(W5O18)2]9– anion to a more thermodynamically stable anion [W12O40(OH)2]10–. Interactions in an aqueous solution of Cu2+ – WO42– – H+(Z = 1,17) – H2O were studied by pH-potentiometric titration methods followed by mathematical modeling according to the CLINP 2.1 program. As an adequate experiment, a model was selected, which included ion pairs [Cu2+, W12O40(OH)2]8– [Cu2+, HW12O40(OH)2]7–, [Cu2+, H2W12O40(OH)2]6–, [Cu2+, H3W12O40(OH)2]5–.
The mixing energies (interaction parameters) and critical decomposition temperatures of Sc1–xLnxVO4 solid solutions with the zircon structure were calculated using the crystal-energy theory of isomorphous miscibility. Diagram of thermodynamic stability visualizing the substitution limits (x) by the decomposition temperature or the decomposition temperature by the substitution limits, the dependencies of the decomposition temperatures on the REE atomic numbers is presented. The results of this study can be used in the development of new luminescent materials based on ScVO4 modified with REE, in the selection of REE for matrix and activator, in defining optimal proportions of REE in Sc1–xLnxVO4 matrices.
Product Description
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Baumer Vyacheslav M.
Borysiuk Karina Yu.
Get'man Yevgen Ivanovych
Duvanova Ella S.
Mariichak Oleksandra Yu.
Oleksii Yuliia A.
Pechalina Yevheniia I.
Popovska Olena Yu.
Radio Serhii V.
Rozantsev Georgiy M.
Tsyba Ilona O.
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2022-03-09
