EFFECT OF ISOVALENT SUBSTITUTION OF EUROPIUM WITH DYSPROSIUM ON THE SLAB STRUCTURE OF SrEu2−xDyxSc2O7 SCANDATES
DOI:
https://doi.org/10.15407/dopovidi2025.01.058Keywords:
compounds of An+1BnO3n+1 type, slab perovskite-like structure, X-ray powder diffractometry, isomorphismAbstract
The dimensions of the phase region with a slab perovskite-like structure in the SrEu2−xDyxSc2O7 system were determined: 0 ≤ х ≤ 0.5 and the crystal structure of the SrEu2−xDyxSc2O7 phases with x = 0.25 and 0.5 was determined using a program based on Rietveld algorithms for multiphase samples. It was established that SrEu2−xDyxSc2O7 samples with x = 0.25 and 0.5 contain two polymorphic modifications with a slab perovskite-like structure: a modification with rhombic syngonia (sp. group Fmmm) and modification with tetragonal syngonia (sp. group I4/mmm). The basis of the slab structure of both modifications of SrEu2−xDyxSc2O7 are two-dimensional perovskite-like blocks with a thickness of two slabs of deformed ScO6 octahedra, which connected by vertices. A slab of (Eu,Dy)O9 polyhedra is located between the blocks and the blocks are connected to each other by bonds —O—(Eu,Dy)—O—. It was established that the increase in the content of dysprosium atoms in SrEu2−xDyxSc2O7 leads to an increase in the degree of deformation of LnO9 interblock polyhedra and a decrease in the Ln—O2 interblock distance. This transformation of the structure destabilizes the interblock space and is one of the main factors in the destruction of the slab perovskite-like structure of SrEu2−xDyxSc2O7 phases at x > 0.5 and leads to the impossibility of SrDy2Sc2O7 scandate existence.
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Schaak, R. E. & Mallouk, T. E. (2002). Perovskites by design: a toolbox of solid-state reactions. Chem. Mater., 14, No. 4, pp. 1455-1471. https://doi.org/10.1021/cm010689m
Lichtenberg, F., Herrnberge, A. & Wiedenmann, K. (2008). Synthesis, structural, magnetic and transport proper- ties of layered perovskite-related titanates, niobates and tantalates of the type AnBnO3n+2, A'Ak−1BkO3k+1 and AmBm−1O3m. Progr. Solid State Chem., 36, No. 4, pp. 253-387. https://doi.org/10.1016/j.progsolidstchem.2008.10.001
Ding, P., Li, W., Li, W., Zhao, H., Wu, C., Zhao, L., Dong, B. & Wang, S. (2021). Review on Ruddlesden—Popper
perovskites as cathode for solid oxide fuel cells. J. Phys. Mater., 4, No. 2, 022002. https://doi.org/10.1088/2515- 7639/abe392
Xiao, H., Liu, P., Wang, W., Ran, R., Zhou, W. & Shao, Z. (2020). Ruddlesden—Popper perovskite oxides for photocatalysis-based water splitting and wastewater treatment. Energy Fuels, 34, No. 8, pp. 9208-9221. https:// doi.org/10.1021/acs.energyfuels.0c02301
He, X., Ma, W., Hong, J., Ba, R. & Li, J. (2022). Microwave dielectric properties of Sr3Ti2O7 ceramics with composite element doping of Nd and Al. Mater. Chem. Phys., 282, 125961. https://doi.org/10.1016/j. matchemphys.2022.125961
Kamimura, S., Yamada, H. & Xu, C.-N. (2012). Strong reddish-orange light emission from stress-activated
+
Srn+1SnnO3n+1:Sm
(n = 1, 2, ∞) with perovskite-related structures. Appl. Phys. Lett., 101, No. 9, 091113.
https://doi.org/10.1063/1.4749807
Kim, I.-S., Kawaji, H., Itoh, M. & Nakamura, T. (1992). Structural and dielectric studies on the new series of layered compounds, strontium lanthanum scandium oxides. Mater. Res. Bull., 27, No. 10, pp. 1193-1203. https://doi.org/10.1016/0025-5408(92)90227-Q
Kim, I.-S., Nakamura, T. & Itoh, M. (1993). Humidity sensing effects of the layered oxides SrO·(LaScO3)n (n = 1, 2, ∞). J. Ceram. Soc. Jap., 101, No. 1175, pp. 800-803. https://doi.org/10.2109/jcersj.101.800
Titov, Y. A., Belyavina, N. N., Markiv, V. Ya., Slobodyanik, M. S., Krayevska, Ya. A. & Chumak, V. V. (2009). Synthesis and determination of the crystal structure of layer scandates SrLn2Sc2O7. Dopov. Nac. akad. nauk Ukr., No. 3, pp. 155-161 (in Ukrainian).
Titov, Y. O., Belyavina, N. M., Slobodyanik, M. S., Chumak, V. V. & Nakonechna, O. I. (2019). Synthesis and crystal structure of isovalently substituted slab SrLa2−xDyxSc2O7 scandates.. Voprosy khimii i khimicheskoi tekhnologii, No. 6, pp. 228-235 (in Ukrainian). https://doi.org/10.32434/0321-4095-2019-127-6-228-235
Titov, Y., Belyavina, N., Slobodyanik, M., Nakonechna, O. & Strutynska, N. (2021). Effect of strontium atoms substitution on the features of two-slab structure of Sr1−xCaxLa2Sc2O7 scandates. French-Ukrainian Journal of Chemistry, 9, No. 1, pp. 44-50. https://doi.org/10.17721/fujcV9I1P44-50
Dashevskyi, M., Boshko, O., Nakonechna, O. & Belyavina, N. (2017). Phase transformations in equiatomic Y—Cu powder mixture at mechanical milling. Metallofiz. Noveishie Tekhnol., 39, No. 4, pp. 541-552. https:// doi.org/10.15407/mfint.39.04.0541
Elcombe, M. M., Kisi, E.H., Hawkins, K.D., White, T.J., Goodman, P. & Matheson, S. (1991). Structure determinations for Ca3Ti2O7, Ca4Ti3O10, Ca3.6Sr0.4Ti3O10 and a refinement of Sr3Ti2O7. Acta Cryst., B47, No. 3, pp. 305-314. https://doi.org/10.1107/S0108768190013416
Shannon, R. D. (1976). Revised effective ionic radii and systematic studies of interatomic distances in halides and halcogenides. Acta Cryst., A32, pp. 751-767. https://doi.org/10.1107/S0567739476001551
Titov, Y. A., Belyavina, N. M., Slobodyanik, M. S., Chumak, V. V., Timosсhenko, M. V. & Sliva, T. Yu. (2020). Effect of isovalent substitution of lanthanum atoms on the slab structure of ВаLa1−xNdxInO4 indates. Dopov. Nac. akad. nauk Ukr., No. 5, pp. 86-94 (in Ukrainian). https://doi.org/10.15407/dopovidi2020.05.086
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