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Information × Registration Number 0220U101353, 0117U001205 , R & D reports Title Active dielectrics and wide-gap semiconductors for solid state ionics, acousto-optics, piezo-technics and sensors. popup.stage_title Head Volnianskyi Mykhailo D., Registration Date 10-02-2020 Organization Oles Honchar Dnipro National University popup.description2  The object of study is physical approaches to increase the efficiency of functional materials by controlling the phase composition, structure and morphology of synthesized compounds, the content of their own defects, alloying, and the use of dimensional phenomena in nano-dispersed systems. The purpose of the work is to establish the physical foundations for creating highly efficient media based on dielectrics and wide-gap semiconductors for solid-state ionics, acousto-optics, and sensors. The research methods were the synthesis of single crystals, glass, glass-ceramics and films of compounds of active dielectrics, differential scanning calorimetry, differential thermal analysis, x-ray phase analysis, methods of dielectric, impedance, optical and radio spectroscopy. It was synthesized samples of compounds Li(Na)2O-xGeO2, PbO-MoO3, TeO2, Na0,5Bi0,5TiО3, BiVO4, Bi12Si(Ge)O20 and АIIВVI (ZnO, etc.), which were analyzed about the mechanisms of the influence of phase composition, morphology, intrinsic defects, and impurities on their electrical properties. The acousto-optic crystals of high quality and laser radiation strength weighing up to 1,6 kg are obtained. For the first time, photoluminescence spectra of crystals and nano-crystalline powders of zinc sulfide doped with manganese were obtained; samples of ceramic structures based on metal oxides have been obtained, which have practical use both as varistors and as gas-sensitive sensors. The effects of hetero-charged alloying and medium inhomogeneity in compounds of lead molybdates and germanates were investigated. Heterophase nanodispersed media with high ionic conductivity have been created. The influence of phase composition and morphology on the electrical properties of Li2O-xGeO2 compounds was revealed, and information on charge carriers and charge transfer mechanisms was obtained. The results of investigation can be used to develop the samples of functional electronics devices. Product Description popup.authors Agarkov Kostyantyn V. Bondar Dmytro S. Bochkova Tetyana M. Dyachenko Anna O. Kovalenko Olexander V. Koptiev Mykhailo M. Panchenko Tetyana V. Rutsky Olexander S. Syetov Evgeny O. Sidak Vasyl M. Trubitsyn Mykhailo P. popup.nrat_date 2020-04-02 Close