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Information × Registration Number 0224U031706, 0122U001953 , R & D reports Title Physico-chemical properties of nanostructured carbon-containing and semiconductor thin-film structures for the needs of renewable hydrogen energy popup.stage_title Head Korotchenkov Oleh O., Доктор фізико-математичних наук Registration Date 06-06-2024 Organization Taras Shevchenko National University of Kyiv popup.description2 A new understanding of heat transfer processes at the porous silicon/ionic liquid interface was obtained. For the first time, a significant increase in the coefficient of thermal conductivity of such a composite system was found - it is 8-10 times higher compared to ionic liquids and 2 times higher compared to porous silicon. A new mechanism for explaining this phenomenon is proposed, which is related to the structuring of the fluid at the interface with porous silicon, which improves heat transfer along the interface. A new original theoretical model is proposed within the effective medium approximation to describe heat transfer in polymer-graphene nanocomposites with nanoparticles decorated graphene sheets. The model takes into account the geometric and material parameters of the filler particles, the contact thermal resistance at the graphene/matrix and graphene/nanoparticle boundaries. The model is also able to predict the temperature dependence of the thermal conductivity in nanocomposites based on the known temperature-dependent parameters of the component phases and contact thermal resistances at their boundaries. It was found that reducing the thickness of the ZnO film deposited on the silicon surface below 70 nm increases the magnitude of the surface photovoltage (SPV) signal (three times in this work) and slows down the kinetics of the SPV relaxation (from 100 µs at thicknesses greater than 70 nm to 10 µs at smaller thicknesses). It was established that this behavior of the SPV signal can be associated with the microstructural transformation in the film with a thickness greater than 70 nm. These results can be explained by the film thickness-dependent concentration of recombination and capture centers of photoexcited charge carriers in the ZnO film and at the ZnO/Si interface. Experimental studies of the decomposition of FeB pairs in silicon solar cells were carried out depending on the power of the light flux and its spectral content. Product Description popup.authors Horb Alla M. Kuzmych Аndrii H. Lishchuk Pavlo O. Maiko Oleksandr M. Nadtochii Andrii B. Polovyna Oleksii I. Saienko Halyna V. Chupryna Roman H. popup.nrat_date 2024-06-06 Close