Registration Number
0221U104267,
0118U003862
, R & D reports
Title
Interface architecture and electronic mechanisms of exciton and excimer formation in multilayer organic light emitting diodes and transistors
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Head
Minaev Boris F., Доктор хімічних наук
Registration Date
11-03-2021
Organization
Bohdan Khmelnytsky National University of Cherkasy
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Purposeful synthesis of new organic molecules and manipulation with the delocalization of electrons in π-conjugate systems allow to change the energy and magnetic parameters of triplet excited states and thus dramatically affect the optical properties of electroluminescent materials. Manipulation of the structure of quinoxaline-based molecules from D-A-D to D-π-A-π-D type leads to a significant improvement in optical and electrochemical properties. These compounds were tested in OLEDs; their external quantum yield reached 4.5% for a deep red nondoped device with a maximum electroluminescence intensity at 662 nm. The use of a host exiplex improves the performance of the device, which leads to an increase in OLED brightness to 20,000 Cd/m2.
Bisindole and biscarbazole anthracenes are effective emitters for blue OLEDs. Zinc(II) complexes with 4-{(E)-[(2-fluorophenyl)imino]methyl}-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one ligand show adjustable luminescence in solution from blue to yellow when changing the wavelength of excitation. An important feature is that the luminescence intensity of these complexes in the solid state can be easily adjusted by replacing the solvent molecules. The concept of conformation-dependent fluorescence has been developed, which has been successfully applied to model new emission tetrabenzo[8]circulenes replaced by electron-accepting groups. These new compounds demonstrate fluorescence on/off in conformational isomerization, which can be very useful for OLED, biovisualization, and sensor applications.
Hetero[8]circulenes have an anisotropic nature of charge transfer for crystals and have attractive semiconductor properties. Tetrabenzoanelated tetraoxa[8]circulene and dianthracenylazatrioxa[8]circulene are effective n-type semiconductors. In general, they can be considered as ambipolar semiconductors, in which the electron conductivity partially dominates over the hole conductivity.
Product Description
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Baryshnikov Glib V.
Baryshnikova Alina T.
Bondarchuk Serhiy V.
Dvirnyk Nikolʹ Yu.
Derevyanko Victoria Yu.
Karaush-Karmazin Nataliia M.
Kuzmishinа Nadiya V.
Minaeva Valentina O.
Melnichаk Alina P.
Pidluzhna Anna Yu.
Ponomarenko Olena V.
Pourets Igor A.
Sakhno Tamara V.
Stakhira Pavel Yo.
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2021-03-17
