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Information × Registration Number 0224U033044, (0123U102727) , R & D reports Title The influence of size effects on the electrophysical properties of graphene-ferroelectric nanostructures popup.stage_title Дослідження кореляції електрофізичного стану графенів з динамічними змінами доменної структури сегнетоелектрика-мультифероїка у комплексах графен-сегнетоелектрик. Head Morozovska Hanna М., Доктор фізико-математичних наук Registration Date 16-12-2024 Organization Institute of Physics of National Academy of Sciences of Ukraine popup.description1 The goal of the project is to establish the influence of size effects on the electrophysical, polar, magnetic and magnetoelectric properties of graphene-ferroelectric nanostructures (GSENS) for the creation of the latest non-volatile memory devices and ultra-sensitive sensors. popup.description2 As a result of the 4-th stage of the project, correlations of the electrophysical state of graphene and/or graphene-like low-dimensional (2D) semiconductors with dynamic changes in the ferroelectric-multiferroic domain structure in graphene-ferroelectric complexes were analyzed. Main new results: 1) Correlations of the electrical conductivity of graphene and the graphene-like 2D semiconductor MoS2 with dynamic changes in the domain structure of nanoscale ferroelectrics-multiferroics, such as nanoparticles of ferrites Fe3O4, orthoferrites LuFeO3 and Bi1-xSmxFeO3, van der Waals ferrielectrics CuInP2S6 and silicon-compatible hafnia oxides HfO2-y with oxygen vacancies and Y impurity, were identified and analyzed. 2) It was established that the ribbons of the layered van der Waals ferroelectric CuInP2S6 exhibit deflection-induced isostructural transitions of the domain structure, which result in the redistribution of the electric field and polarization, mechanical stresses and deformations. The electrical conductivity of graphene and/or graphene-like 2D semiconductor MoS2 correlates with dynamic changes in the domain structure of van der Waals ferrielectric ribbons. 3) It has been established that an increase in the content of oxygen vacancies (which are mainly located on the surface and near the surface of nanoparticles) leads to the appearance of orthorhombic phases (among which is the polar phase Pca21) in HfO2-y nanoparticles, and the content of orthorhombic phases increases above 80% in the presence of a high concentration of oxygen vacancies ("y" more than 3 - 5%). The electrical conductivity of graphene in a complex with HfO2-y nanoparticles correlates with dynamic changes in the domain structure of nanoparticles. 4) The most promising of the investigated graphene-ferroelectric nanostructures and their complexes are proposed, in particular nanocomposites containing Bi1-xSmxFeO3 nanoparticles (chemical composition 5% ≤ x < 15%) in polymer matrices. Product Description popup.authors Bodnaruk Andrii V. Leonenko Yevhen V. Morozovska Hanna M. Pylypchuk Oleksandr S. Ralliev Maksym V. Starynets Serhii M. Tkachenko Vitalii S. Fesenko Olena M. Yaremkevych Andrii D. popup.nrat_date 2024-12-16 Close