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Information × Registration Number 0215U001232, 0112U001291 , R & D reports Title Luminescence of the isoelectronic impurities in oxides with different structural types popup.stage_title Head Zorenko Yuriy, Registration Date 03-02-2015 Organization Ivan Franko National University of Lviv popup.description2 The regularities of radiative relaxation of the low-energy excitations in the luminescent oxide materials based on the А3Al5О12 garnets, АAlО3 perovskites and A2SiO5 orthosilicates, (A=Y, Lu), doped with Sc3+ and La3+isoelectronic impurities (IsIm), as well as the sapphire Al2O3, doped with Sc3+ and Ga3+ IsIm, have been considered in this work. We have also studied the energy transfer processes in the mentioned oxide materials doped by the IsIm and co-doped with rare-earth (Се3+, Pr3+ і Tb3+) ions. The nature of emission centers, their energy structure as well as the energy transfer processes in the oxide compounds under study were investigated using the traditional spectral methods and the time-resolved luminescent spectroscopy under excitation by synchrotron radiation with energy in the 3.7-25 еV range at 8-300 К temperatures. The investigations within the project also included the following original technological works: (i) the crystallization of the single Sc3+ and La3+ doped or double Sc/La-Се/Pr/Tb doped single crystalline films (SCF) of YAG and LuAG garnets, YAP and LuAP perovskites and YSO and LSO orthosilicates as well as Sc3+ and Ga3+ doped ?-Al2O3 sapphire using the Liquid Phase Epitaxy (LPE) method; (ii) the synthesis of the crystalline micro- and nano-powder analogs of mentioned compounds using the solid-state reactions; (iii) the investigations of the luminescence center formation in the compounds under study depending on the conditions of their preparation and concentration of IsIm and rare-earth dopants. The investigations performed within the project result in the determination of the nature of different types of the luminescence centers, created by the Sc3+ і La3+ IsIm in the cation positions of the garnet, perovskite, orthosilicate and sapphire hosts. We have also proposed the conceptual approach to formation of the emission centers in the oxide compounds doped with the IsIm. This concept is based on the conclusion about creation by the IsIm of two types of emission centers in the oxide compounds: the luminescence of the excitons, localized around IsIm prevails at low (0.5-1 at. %) concentration of IsIm, whereas at larger concentration of dopants the recombination luminescence of electron-hole pairs directly at IsIm dominates. The last luminescence can be interpreted as radiative relaxation of the excitons bound with the IsIms. In 2012-2014, the participants of the project published 63 papers, including 41 papers in the JCR journals. The results of the project have also been presented in 47 reports at international conferences in the field of research. The PhD work was defended in 2012 by the participant of the project, dr Voznyak Taras at scientific council D 64.169.01 at the Institute for Single Crystals of Ukrainian National Academy of Sciences in Kharkiv. Product Description popup.authors Горбенко Віталій Іванович popup.nrat_date 2020-04-02 Close