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Information × Registration Number 0220U100960, 0119U001744 , R & D reports Title Electronic transport in advanced high-mobility thin-films organic semiconductors: from hopping to band-like mechanism. popup.stage_title Head Kadashchuk Andrii K., Registration Date 30-01-2020 Organization Institute of physics of NAS of Ukraine popup.description2 The aim of the research project was the combined study, by means of the wide set of the spectral, electrical and structural methods, of the energy distribution of trap states for the charge carriers, the energy position of the excitonic levels, as well the luminescent and electroluminescent properties of the thin films of organometallic perovskites depending on the dimension of crystal structure and on the films’ morphology. It was established that in thin films of perovskite with quasi-2D polycrystalline structure the density of trap states for charge carriers is much greater and their energy distribution is considerably wider in comparison with the perovskite films of similar chemical composition but with the three-dimensional (3D) structure. This difference is caused by the presence of the nanosized domains of 3D phase in the films with 2D structure, which do not only produce the deep traps for charge carriers but also act as the centers for charge recombination and in such a way facilitate a capture of excitons that in turn reduces the loss from the radiationless recombination. The optimization of the abundance and the size of 3D-domains, as well as the refinement of the quality of crystal structure of the films, result in the substantial improvement of the electrical parameters of the light-emitting diods (LEDs) due to the far more uniform distribution of space charge within the active perovkite layer as a consequence of the balance of electron and hole currents. These results are novel and principally significant for a better insight of the photophysical processes, which occur in LEDs based on the hybrid metal-organic perovskites, and also they open the technological potentialities for making the LEDs with better parameters than those of the present, state-of-the-art devices. Product Description popup.authors Vakhnin Alexander Yu. Kadashchuk Andrey K. popup.nrat_date 2020-04-02 Close