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Information × Registration Number 0223U005454, 0123U103547 , R & D reports Title Environmentally safe piezo/ferroelectric flexible nanocomposites for converting mechanical load into light and electrical energy popup.stage_title Head Lazarenko Maksym M., Доктор фізико-математичних наук Registration Date 22-12-2023 Organization Taras Shevchenko National University of Kyiv popup.description2 Object of study: piezo/ferroelectric flexible nanocomposites. Aim of work: Elaboration of piezoelectric flexible environmentally safe ("green") hybrid composites that respond to external mechanical loads with two different types of signals: piezoelectric (PzE) and mechanoluminescent (ML). Research methods: structural, optical, electrical, mechanical and thermophysical research. Technological parameters of production were optimized and the main characteristics of suspensions of micro/nano-sized cellulose (MNCel) extracted from various plant materials and by various methods were determined. Peculiarities of formation and optimal conditions for the synthesis of concentration series of highly homogeneous stoichiometric luminescent ferro-piezoelectrics Bi3-xPrxTiNbO9, Bi4-xPrxTi3O12 and Pb(Zr,Ti)O3:Pr were determined. Conditions of synthesis were determined and micro/nanosized oxides based on gadolinium and scandium K2(Sc/Gd)2P2MoO12, doped with europium, were synthesized in amount necessary for production of composites. A series of binary composites was produced: "luminescent oxide-MNCel"; "luminescent PzE-oxide - MNCel"; "carbon nanotubes - MNCel". A series of binary composites made on the basis of a mixed polymer matrix (MNCel + PVA) / (MNCel + Liquid Glass (LG)), luminescent oxides and BaTiO3, Ca/SrAl2O4 oxides doped with Eu, Dy, Pr ions were studied. The effect of temperature, moisture and electromagnetic field frequency on the complex dielectric constant of MNCel films and manufactured composites was determined. The models for calculating the interactions of surface fragments of binary composites were determined: "cellulose molecules - oxide luminescent groups" and "cellulose molecules - carbon nanostructures". Equipment was upgraded and the ML and PzE properties of selected samples of components and composites were investigated under static (compression) and dynamic (ultrasound field with frequencies of 20kHz and 1.4MHz) mechanical loading.  Product Description popup.authors Andrusenko Dmytro A. Barbash Valerii A. Borysiuk Viktor I. Gerasimchuk Danylo О. Hnatyuk Kateryna I. Zozulya Valeria О. Nedilko Serhii H. Sosnovska Mariya О. Titov Yuriy О. Kateryna V. Terebilenko Khyzhnyi Yurii A. Chorniy Vitaliy Р. Yashchenko Olha V. popup.nrat_date 2023-12-22 Close