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Information × Registration Number 0220U100008, 0119U101351 , R & D reports Title Dielectric materials with high permittivity based on spontaneously polarized systems, lithium conductors and transition metal oxides popup.stage_title Head Bilous Anatoliy G., Доктор хімічних наук Registration Date 02-01-2020 Organization V.I. Vernadskii Institute of General & Inorganic Chemistry NAS of Ukraine popup.description2 The aim of the work is the development of materials with high dielectric constant (> 1000), which is manifested in wide temperature and frequency ranges based on three types of complex oxides: spontaneously polarized systems; lithium-conducting systems as well as transition-metals-based oxides. In the reporting period, samples based on spontaneously polarized systems were studied. It was found that Ba1-xLnxTi1-x/4O3 (Ln = La, Nd) solid solutions exist in the concentration range 0.05 <x <0.07, in which partial substitution of barium ions by ions of R.E. is accompanied by the formation of structural vacancies in the titanium lattice. In the area, where solid solutions Ba1-xLnxTi1-x/4O3 exist, the phase transition temperature decreases and an in the maximum value of the dielectric constant increases with increasing degree of substitution (x). At 0.05 <x <0.07, regardless of the rare-earth ion nature, the transition to a spontaneously polarized state occurs below room temperature. The synthesized materials show a record high value of dielectric constant and insignificant dielectric losses. The sequence of phase transformations in the synthesis by the method of solid-phase reactions of solid solutions of Ba(Ti,Sn)O3 was established, and crystallographic and microscopic studies of polycrystalline ceramics based on solid solutions of Ba(Ti,Sn)O3 were performed. It was found that with the additional introduction of 0.5 wt.% Manganese oxide (IV) and 2 wt. % of fusible glass-forming impurity AST (Al2O3-SiO2-TiO2) can improve the dielectric parameters (permittivity and losses) and reduce the sintering temperature of ceramics based on Ba(Ti,Sn)O3. It was shown that the prepared materials are promising for the creation of ceramic capacitors based on them. Product Description popup.authors V'yunov Oleg I. popup.nrat_date 2020-04-02 Close