A5028914055- Organic Light-Emitting Diodes Research
- Organic Electronics and Photovoltaics
- Luminescence and Fluorescent Materials
- Conducting polymers and applications
- Photochemistry and Electron Transfer Studies
- Crystallization and Solubility Studies
- Photochromic and Fluorescence Chemistry
- Synthesis and properties of polymers
- X-ray Diffraction in Crystallography
- Photopolymerization techniques and applications
- Advanced Polymer Synthesis and Characterization
- Molecular Junctions and Nanostructures
- Lanthanide and Transition Metal Complexes
- Perovskite Materials and Applications
- Epoxy Resin Curing Processes
- Thin-Film Transistor Technologies
- Molecular Sensors and Ion Detection
- Synthesis and Characterization of Heterocyclic Compounds
- Fluorine in Organic Chemistry
- Catalytic Cross-Coupling Reactions
- Phenothiazines and Benzothiazines Synthesis and Activities
- Polydiacetylene-based materials and applications
- Silicone and Siloxane Chemistry
- Nonlinear Optical Materials Research
- Organoselenium and organotellurium chemistry
Kaunas University of Technology
2015-2024
National University of Singapore
2010
Vilnius University
2010
Universitat Rovira i Virgili
2008
Linking topology in oligocarbazoles (see figure) has a strong influence on their electronic properties. 3(6),9′-linked exhibit unusual suppression of coupling between units, leading to localized excited states and very small reduction triplet energies (compared the monomer). Coupled with excellent morphological stability, this makes them suitable as host materials for blue electrophosphorescence devices. Supporting information article is available WWW under...
The starburst carbazole derivative and phosphorescent bis-cyclometalated iridium(III) complex (IC2) were used for the preparation of multilayered "warm-white" organic light-emitting diodes (OLEDs), emission spectra which are modulated by thickness layer. It was shown that electroluminescence fabricated devices more extended into visible region compared with photoluminescence both component materials. observed extension can be assigned to low-energy exciplex formed at interface emissive...
Aiming to design bipolar organic semiconductors with high electron mobility and efficient red thermally activated delayed fluorescence (TADF), three donor-acceptor compounds were designed synthesized selecting 1,8-naphthalimide as an acceptor phenoxazine, 3,7-di-tert-butylphenothiazine or 2,7-di-tert-butyldimethyl-9,10-dihydroacridine donor moieties. Aggregation induced emission enhancement was detected for the causing TADF in solid-state. Photoluminescence quantum yields up 77% observed...
Motivated to minimize the effects of solid-state solvation and conformation disorder on emission properties donor-acceptor-type emitters, we developed five new asymmetric multiple donor-acceptor type derivatives tert-butyl carbazole trifluoromethyl benzene exploiting different electron-accepting anchoring groups. Using this design strategy, for a compound containing four di-tert-butyl units as donors well 5-methyl pyrimidine acceptor moieties, small singlet-triplet splitting ca. 0.03 eV,...
The synthesis and properties of two derivatives 1-phenyl-1H-benzo[d]imidazole with differing numbers tert-butylcarbazole electron-donating moieties are reported. compounds exhibit high thermal stability, 5% weight loss temperatures exceeding...
Carbazolyl and phenothiazinyl tetra substituted derivatives of pyrene, namely, 1,3,6,8-tetra(9-ethyl-9H-carbazol-3-yl) pyrene (1), 1,3,6,8-tetra(9-ethyl-9H-carbazol-2-yl) (2), 1,3,6,8-tetra(10-ethyl-10H-phenothiazin-3-yl) (3) 1,3,6,8-tetra(9-dodecyl-9H-carbazol-3-yl) (4), were synthesized characterized. They displayed excellent thermal stability, with the onsets degradation well exceeding 400 °C, demonstrated glass transitions between 32 232 °C. Pyrene carbazole arms shown to be highly...
The single-layer and bilayer devices showed blue monomer, electromer or interface exciplex emission.
Two derivatives of tetrafluorophenylcarbazole and tri/tetraphenylethylene displaying aggregation-induced emission enhancement were synthesized investigated by theoretical experimental tools. The compounds exhibit efficient in solid state with fluorescence intensity maxima at 511 502 nm photoluminescence quantum yields 57 27%. They high thermal stability 5% weight loss temperatures 362 314 °C glass-forming properties glass-transition 112 80 °C. Ionization potentials measured photoelectron...
Abstract Two phenothiazine‐based electroactive compounds were synthesized by Buchwald‐Hartwig cross‐coupling reaction. The consist of pyridine‐ or benzonitrile accepting moiety and phenothiazine donor fragments linked through tertiary amino linkage. resulting showed high thermal stability with 10 % weight loss temperatures 270 308 °C. Both the reversible oxidation after repeated scans cyclic voltammetry. Experimental results in combination outcomes TD‐DFT calculations, employed to examine...
A series of perylenediimide-based small molecules (PDI1−PDI5) containing electron-deficient groups in the bay region were synthesized and characterized. The PDI derivatives found to be capable forming molecular glasses with glass transition temperatures ranging from 50 102 °C. Detailed investigations optical properties performed compared those obtained quantum chemical calculations. Optimized structures exhibited core-twisting by 16° torsional angle between substituent perylene core range...
The synthesis and full characterization of new derivatives indolo[3,2-b]carbazole with differently substituted phenyl groups at nitrogen atoms is reported. Comparative study on their thermal, optical electrochemical, photoelectrical properties presented. synthesized compounds are electrochemically stable. Their highest occupied molecular orbital energy values range from -5.14 to -5.07 eV. electron photoemission spectra the films materials revealed ionization potentials 5.31-5.47 Hole drift...
Three new isomeric cyclohexylidene linked triphenylamines containing methoxy groups in different positions were synthesized via Ullmann coupling from 1,1-bis(4-aminophenyl)cyclohexane and respective aryl iodides. Thermal behaviour, optical photoelectrical properties of the obtained materials investigated. Calculations based on density functional methods (DFT) also carried out order to better understand structure–property relationships. Methoxy-substituted derivatives show lower ionization...
The synthesis and properties of carbazole diphenylamine derivatives with different numbers positions methoxy groups in the diphenylamino moiety are reported. A comparative study on their thermal, optical, photoelectrical is presented. All synthesized compounds found to form glasses glass transition temperatures range 39−69 °C, as characterized by differential scanning calorimetry. ionization potentials were estimated both theoretically quantum chemical calculations experimentally an electron...
Excited state dynamics of trinary star-shaped dendritic compounds with triphenylamine arms and different cores were studied by means time-resolved fluorescence transient absorption. Under optical excitation, nonpolar C3 symmetry molecules form polar excited states localized on one the molecular substituents. Conformational stabilization an electron-accepting core causes a formation twisted internal charge transfer (TICT) in solvents. A low transition dipole moment from TICT to ground very...
The synthesis of new iridium(III) complexes containing a 2-(benzo[b]selenophen-2-yl)pyridine ligand is reported along with their photophysical, thermal, electrochemical and electroluminescent properties. These are characterized by deep red phosphorescence photoluminescence quantum yields exceeding 31% in the solid state. Solid layers were ionization potentials 5.17-5.27 eV electron affinities 2.87-2.95 eV. Their thermal stabilities proved cyclic voltammetry thermogravimetric analysis. Deep...
Capability of exciplex energy transfer through a spacer was investigated using three exciplex-forming solid mixtures which contained the well-known electron accepting 2,4,6-tris[3-(diphenylphosphinyl)phenyl]-1,3,5-triazine and appropriately designed bipolar cyanocarbazolyl-based derivatives functionalized by attachment carbazolyl, acridanyl or phenyl units. These novel were used as both donor. Efficient organic light-emitting diodes with electroluminescence in cyan-yellow region maximum...