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Information × Registration Number 0218U001450, 0115U000637 , R & D reports Title Structural and spectral properties of new materials for dye sensitized solar cells, nanophotonics and organic light emitting devices. popup.stage_title Head Minaiev Borуs Pylypovych, Registration Date 09-02-2018 Organization B. Khmelnitsky state university in Cherkasy popup.description2 The aim of this work is quantum-chemical studies of the structure, photophysical and semiconductor properties of new materials for organic light-emitting devices (OLED) and dye-sensitized solar cells (DSSC) and establishing the interdependence between the structure of molecules and its absorption/emission spectra. Object of study - series of organic sensitizing dyes for DSSC of indoline and triphenylamine series with modified donor, bridging and acceptor fragments, as well as new high-efficiency emitters of heterocirculenes, diphenylaminocarbazoles, 1,2,4-triazole derivatives and their complexes with transition metals and lanthanides, complexes Ir(III). Research methods: 1) classical physicochemical methods, such as UV-visible and IR spectroscopy, NMR spectroscopy, EPR, mass spectrometry, powder X-ray diffractometry, X-ray diffraction analysis, thermogravimetric analysis, high-precision deposition techniques and others; 2) modern methods of quantum chemistry, such as density functional theory - DFT and its nonstationary version - TDDFT, ab initio methods such as RI-CC2 and XMC-QDPT2, Beyder's theory of "Atoms in molecules" and others. Main scientific results: 1. It was found that heterocirculene molecules are characterized by the presence of a concentric system of paratropic (anti-aromatic) and diatropic (aromatic) magnetic ring currents. 2. It is proved that the intensity of the first electronic transition S0?S1 in the absorption spectra of the studied heterocirculenes increases significantly due to vibrational interactions. 3. The effect of NH/O substitution and conjugation degree on the fluorescence quantum yield was revealed for a series of heterocirculenes. In this respect, asatrioxa[8]circulenes show significantly higher values the fluorescence quantum yield than their oxygen substituted analogs. 4. Multilayered OLED devices with white color of luminescence based on benzoannelated azatrioxa[8]circulenes were constructed and tested. 5. It was found two new polymorphic forms of carbon nitride stoichiometry (1:1) of the space group P3m1 which are semiconductors with a indirect wide band gap. 6. It was fabricated new organic light-emitting devices, which are based on exciplex radiation generated at the phase boundary of star-shaped organic emitters (mainly circulenes and carbazole derivatives). 8. It was fabricated new high-performance organic light-emitting diodes with a blue color glow, in which the binindole condensed derivatives were used as emission materials. Product Description popup.authors Баришніков Гліб Володимирович Бондарчук Сергій Вікторович Карауш Наталія Миколаївна Мінаєва Валентина Олександрівна popup.nrat_date 2020-04-02 Close