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Information × Registration Number 0221U103084, 0119U100316 , R & D reports Title Crystal-chemical design and functional properties of new complex oxide compounds and hybrid nanostructures on their basis. popup.stage_title Head Slobodyanik Nikolay S., Доктор хімічних наук Registration Date 14-02-2021 Organization Taras Shevchenko National University of Kyiv popup.description2 Object of research: complex oxide compounds based on variously charged anions (phosphates, vanadates, molybdates), compounds and isomorphically substituted phases with a layered perovskite-like structure are suitable for the development of functional materials for various purposes. Purpose: to investigate the structure and characteristics of IR and electronic spectra, luminescent, optical and thermal properties, as well as the bioactivity of new complex oxide compounds and hybrid nanostructures. Research methods: X-ray diffraction analysis, powder X-ray diffractometry methods, IR and electron spectroscopy, thermogravimetric method and research of antimicrobial and mechanical properties of synthesized compounds. For the phases MI0.5xBi1-0.5x (MoxV1-x) O4 and SrxBi1-xV1-xMoxO4 in the case of Na / Bi Sr / Bi pairs the tetragonal symmetry of the scheelite framework is preserved, and for K / Bi and Ca / Bi limited solid solutions with different the degree of monoclinic deformation of the lattice. It is shown that the increase of vanadium content in the systems leads to a decrease in the band gap from 2.85 to 2.22 eV. The highest photoluminescence intensity is set for K0.5xBi1-0.5x (MoxV1-x) O4: Eu (monoclinic syngony) and is associated with the supersensitive transition 5D0 → 7F2, which indicates a low-symmetric environment of Eu ions (III). It is established that for the Sr9Bi (PO4) 7-x (VO4) x phases the structure of the palmyerite type is stabilized with partial substitution of SrBi and 70% (PO4)  (VO4), and in the absence of vanadate the mixture of phases is formed. Isovalent substitution in the anionic sublattice of the Sr9Bi (PO4) 2 (VO4) 5 matrix helps to reduce the band gap to 3.0 eV (for Sr9Bi (VO4) 7), which indicates the prospects for further search for effective photocatalysts based on Sr and Bi phosphate vanadates.  Product Description popup.authors Voytenko Tetyana A. Hrynyuk Iryna І. Dziazko Oleksandr G. Zelen'ko Mykola Anatolijovych Prylutsʹka Svitlana V. Slyva Tetyana Yu. Strutynska Nataliia Yu. Titov Yuriy О. Terebilenko Kateryna V. Fesych Igor V. popup.nrat_date 2021-02-14 Close