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Information × Registration Number 0220U100493, 0119U103986 , R & D reports Title Optimization of technology of growing perovskite semiconductor crystals CsPbBr3. popup.stage_title Head Kanak Andrii I., Registration Date 20-01-2020 Organization Yuriy Fedkovych Chernivtsi National University popup.description2  The object of the study is the phase equilibria of CsPbBr3 perovskite, the electrical and optical properties of Cesium Plumbum bromide crystals. Purpose: Optimization of Bridgman vertical growing technology for CsPbBr3 single crystals. Obtaining materials with a high degree of single crystallinity and predetermined electrical and optical properties. Research methods: differential thermal analysis (DTA), crystal growth (Bridgman's vertical method), electrical measurements (volt-ampere measurements,) optical measurements (measurements of optical absorption, photoluminescence and time dependence of the integral photoluminescence intensity). The crystalline CsPbBr3 was synthesized by the mechanochemical method with further fusion. Processes of melting and crystallization of the obtained perovskite were investigated using differential thermal analysis with heating/cooling rates of 0.1, 1, 3, 5 and 10 ° C / min. A decrease in the melting point from 568.2 ± 0.1 ° C to 566.3 ± 0.2 ° C was observed with an increase in the heating rate from 0.1 ° C / min. up to 10 ° C / min. respectively. The idea of ​​a two-stage melting mechanism of CsPbBr3 perovskite with an initial stage of fragmentation of the crystalline structure and subsequent dissolution of crystalline phase residues is proposed. It is reported that when the melt is heated above a certain "critical" temperature (579-585 ° C), its homogenization occurs, and the crystallization temperature is set at 540-550 ° C for a heating/cooling rate of 0.1-1 ° C / min. and 538-543 ° C for speeds of 5-10 ° C / min. The data obtained were used to optimize the technology of growing CsPbBr3 crystals. The measured resistivity of the obtained samples was at the level of 4-5 × 10^9 Ohm × cm, the width of the bandgap was 2.24 eV. The lifetime of the charge carriers was 27 ns when excited by a laser with a wavelength of 402 nm. Product Description popup.authors Solodin Serhii V. popup.nrat_date 2020-04-02 Close