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Information × Registration Number 0221U106603, 0120U104771 , R & D reports Title Structure transformation and non-equilibrium electron processes in wide bandgap metal oxides and their solid solutions popup.stage_title Head Melnychuk Oleksandr V., Доктор фізико-математичних наук Registration Date 15-12-2021 Organization Nizhyn Mykola Gogol State University popup.description2 Research object – polycrystalline solid solutions MgxZn1–xO ceramics, undoped and doped ZrO2. Research subject – evolution of structural, optical, electrical and luminescent properties of materials based on doped oxides and their solid solutions versus the fabrication conditions and subsequent heat treatment. The aim of the work is to elucidate the nature of physical phenomena occurring in powders, layers and ceramics of wide bandgap metal oxides and their solid solutions governed by their doping and subsequent various treatments, as well as to develop the theory of infrared radiation interaction with polycrystalline materials. Research methods – optical, luminescent, electrical, X-ray diffraction, Raman scattering, scanning electron microscopy, Auger spectroscopy. Results and their novelty: It is shown that doping of MgxZn1–xO ceramics with Zn substituting acceptors (Li, Cu, Ag, Na) results in the enhancement of photoluminescence in visible spectra range. It is found that at room temperature the photoconductivity of ZnO and MgxZn1–xO ceramics doped with acceptors up to 1020 cm–3 is absent, but is observed at a temperature of 77 K. It is established that the lack of photoconductivity at room temperature is due to the high concentration of equilibrium electrons in ceramic grains. The dependence of the degree of equilibrium conductivity compensation depends on the annealing temperature, concentration and type of acceptor impurity of group 1, as well as the material of the substrate on which the ceramic is sintered is found. For the first time, the possibility of excitation and propagation of surface polaritons in ZnMgO ceramics by the method of attenuated total reflection has been shown. Types of impurities and modes of heat treatment that allow obtaining ZrO2 with cubic structure are determined. The relationship between the crystal structure, the degree of doping and the optical and recombination properties of the samples is established. Product Description popup.authors Zahorodnia Tetiana P. Kozoriz Kostyantyn O. Melnychuk Lyudmyla Yu Polishchuk Yuliia O Ponomaryov Semen S. Khomenkova Larysa Yu. popup.nrat_date 2021-12-15 Close