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Information × Registration Number 0223U001178, 0122U001959 , R & D reports Title Structural aspects of optimization of functional properties of complex oxide compounds for modern phosphors, ionic conductors and magnetic materials popup.stage_title Head Slobodianyk Mykola S., Доктор хімічних наук Registration Date 25-01-2023 Organization Taras Shevchenko National University of Kyiv popup.description2 Research object: Complex oxide compounds with tetrahedral anions (phosphate, vanadate, molybdate, tungstate), as well as phases of the type An+1BnO3n+1 with a 2D type of layered perovskite-like structure. The purpose of the work: to synthesize new complex oxide compounds with tetrahedral anions (phosphates, molybdates, tungstates) and isomorphosubstituted phases with a layered perovskite-like structure by methods of melt, solution-melt, solid-phase synthesis and co-precipitation and their characterization by physicochemical research methods. Research methods: chemical analysis, pH-metry, X-ray powder diffractometry methods, SEM, energy-dispersive X-ray spectroscopy, IR and electron spectroscopy, thermogravimetric method. The formation conditions were found and a number of new compounds were synthesized: K2Ln(PO4)(AO4) (A – Mo, W; Ln – Gd-Tb), glass ceramics of the composition K2O–P2O5–Eu2O3–WO3–V2O5, as well as modified calcium phosphates of the white-kite type in including biphasic compositions. It was established that the K/W ratio of 1.2–1.5 is key for the formation of K2Ln(PO4)(WO4) (Ln – Gd-Tb) compounds with a layered structure. For glass-ceramics of the composition K2O–P2O5–Eu2O3–WO3–V2O5, a synergistic effect of the influence of V2O5 concentration on luminescence was shown, and it was found that VO4 groups act as centers of absorption of exciting radiation and effectively transmit it to Eu3+ - luminescence centers. The conditions of production, boundaries of the regions of existence were established, and isomorphosubstituted phases with SHPS were synthesized in systems of the type AIILa1-xLnxBIIIO4, A1-xA*xLn2BIII 2O7, AIILn2-xLn*xBIII 2O7 (A = Sr, Ba, A* = Ca, Sr, Ln = La , Pr, Nd, Ln* = Sm, Dy, BIII = Sc, In). The obtained results are the basis for the development of technologies for the synthesis of compounds and phases of the type An+1B III nO3n+1 with SHPS and the purposeful search and regulation of the functional properties of materials based on them.  Product Description popup.authors Strutynska Nataliia Yu. Titov Yuriy О. Terebilenko Kateryna V. Tymoshenko Mar'yana V. Fesych Igor V. popup.nrat_date 2023-01-25 Close