Platinum-Functionalized Chiral Molecular Squares as Light-Emitting Materials

2004 ◽  
Vol 846 ◽  
Author(s):  
Lin Zhang ◽  
Yu-Hua Niu ◽  
Alex K.-Y. Jen ◽  
Wenbin Lin
Keyword(s):  
Mass Spectrometry ◽  
Luminous Efficiency ◽  
Quantum Yields ◽  
Bridging Ligands ◽  
Maximum Brightness ◽  
Light Emitting ◽  
Visible Luminescence ◽  
Molecular Squares ◽  
Uv Visible ◽  
C Nmr

ABSTRACTA family of new chiral metallocycles based on Pt(II) diimine metallocornors and bis(acetylene) bridging ligands have been synthesized, and characterized by a variety of techniques including 1H and 13C NMR, UV-visible, luminescence, infrared, and circular dichroism (CD) spectroscopies, and mass spectrometry. All metallocycles exhibit very strong phosphorescence with quantum yields of 8.3 to 15.7%. Chiral Pt(II)-based molecular squares were used as the light-emitting layer in multiplayer devices, and a maximum brightness of 5470 cd/m2 with a maximum luminous efficiency of 0.93 cd/A was achieved.

scholarly journals Simple Synthesis of Red Iridium(III) Complexes with Sulfur-Contained Four-Membered Ancillary Ligands for OLEDs

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2599
Author(s):  
Meng-Xi Mao ◽  
Fang-Ling Li ◽  
Yan Shen ◽  
Qi-Ming Liu ◽  
Shuai Xing ◽  
...  
Keyword(s):  
Indium Tin Oxide ◽  
Quantum Yields ◽  
Rapid Preparation ◽  
Maximum Brightness ◽  
Ancillary Ligands ◽  
Light Emitting ◽  
Maximum Current ◽  
Electron Donating Groups ◽  
Sulfur Containing ◽  
Main Ligand

Phosphorescent iridium(III) complexes have been widely researched for the fabrication of efficient organic light-emitting diodes (OLEDs). In this work, three red Ir(III) complexes named Ir-1, Ir-2, and Ir-3, with Ir-S-C-S four-membered framework rings, were synthesized efficiently at room temperature within 5 min using sulfur-containing ancillary ligands with electron-donating groups of 9,10-dihydro-9,9-dimethylacridine, phenoxazine, and phenothiazine, respectively. Due to the same main ligand of 4-(4-(trifluoromethyl)phenyl)quinazoline, all Ir(III) complexes showed similar photoluminescence emissions at 622, 619, and 622 nm with phosphorescence quantum yields of 35.4%, 50.4%, and 52.8%, respectively. OLEDs employing these complexes as emitters with the structure of ITO (indium tin oxide)/HAT-CN (dipyra-zino[2,3-f,2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile, 5 nm)/TAPC (4,4′-cyclohexylidenebis[N,N-bis-(4-methylphenyl)aniline], 40 nm)/TCTA (4,4″,4″-tris(carbazol-9-yl)triphenylamine, 10 nm)/Ir(III) complex (10 wt%): 2,6DCzPPy (2,6-bis-(3-(carbazol-9-yl)phenyl)pyridine, 10 nm)/TmPyPB (1,3,5-tri(mpyrid-3-yl-phenyl)benzene, 50 nm)/LiF (1 nm)/Al (100 nm) achieved good performance. In particular, the device based on complex Ir-3 with the phenothiazine unit showed the best performance with a maximum brightness of 22,480 cd m−2, a maximum current efficiency of 23.71 cd A−1, and a maximum external quantum efficiency of 18.1%. The research results suggest the Ir(III) complexes with a four-membered ring Ir-S-C-S backbone provide ideas for the rapid preparation of Ir(III) complexes for OLEDs.

scholarly journals New Unsymmetrically Substituted Benzothiadiazole-Based Luminophores: Synthesis, Optical, Electrochemical Studies, Charge Transport, and Electroluminescent Characteristics

Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7596
Author(s):  
Pavel S. Gribanov ◽  
Dmitry A. Loginov ◽  
Dmitry A. Lypenko ◽  
Artem V. Dmitriev ◽  
Sergey I. Pozin ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Charge Transport ◽  
Active Transport ◽  
Cross Coupling ◽  
Luminous Efficiency ◽  
Charge Carriers ◽  
Quantum Yields ◽  
Electrochemical Studies ◽  
Light Emitting ◽  
Photoluminescence Quantum Yield

Three new benzothiadiazole (BTD)-containing luminophores with different configurations of aryl linkers have been prepared via Pd-catalyzed cross-coupling Suzuki and Buchwald–Hartwig reactions. Photophysical and electroluminescent properties of the compounds were investigated to estimate their potential for optoelectronic applications. All synthesized structures have sufficiently high quantum yields in film. The BTD with aryl bridged carbazole unit demonstrated the highest electrons and holes mobility in a series. OLED with light-emitting layer (EML) based on this compound exhibited the highest brightness, as well as current and luminous efficiency. The synthesized compounds are not only luminophores with a high photoluminescence quantum yield, but also active transport centers for charge carriers in EML of OLED devices.

Novel hole transport materials based on N,N′-disubstituted-dihydrophenazine derivatives for electroluminescent diodes

2014 ◽  
Vol 2 (46) ◽  
pp. 9858-9865 ◽  
Author(s):  
Zhiwen Zheng ◽  
Qingchen Dong ◽  
Liao Gou ◽  
Jian-Hua Su ◽  
Jinhai Huang
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Crystal Structure Analysis ◽  
Hole Transport ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
H Nmr ◽  
Organic Light ◽  
Single Crystal Structure Analysis ◽  
C Nmr

A series of novel hole transport materials for organic light-emitting diodes (OLEDs) based on 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine were synthesized and characterized by 1H NMR and 13C NMR, mass spectrometry and single crystal structure analysis methodologies.

scholarly journals New Phosphine Oxides as High Performance Near- UV Type I Photoinitiators of Radical Polymerization

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1671 ◽  
Author(s):  
Céline Dietlin ◽  
Thanh Tam Trinh ◽  
Stéphane Schweizer ◽  
Bernadette Graff ◽  
Fabrice Morlet-Savary ◽  
...  
Keyword(s):  
Light Absorption ◽  
High Performance ◽  
Uv Light ◽  
Quantum Yields ◽  
Type I ◽  
Phosphine Oxides ◽  
Absorption Properties ◽  
Light Emitting ◽  
Uv Visible ◽  
Led Irradiation

Carbazole structures are of high interest in photopolymerization due to their enhanced light absorption properties in the near-UV or even visible ranges. Therefore, type I photoinitiators combining the carbazole chromophore to the well-established phosphine-oxides were proposed and studied in this article. The aim of this article was to propose type I photoinitiators that can be more reactive than benchmark phosphine oxides, which are among the more reactive type I photoinitiators for a UV or near-UV light emitting diodes (LED) irradiation. Two molecules were synthesized and their UV-visible light absorption properties as well as the quantum yields of photolysis and photopolymerization performances were measured. Remarkably, the associated absorption was enhanced in the 350–410 nm range compared to benchmark phosphine oxides, and one compound was found to be more reactive in photopolymerization than the commercial photoinitiator TPO-L for an irradiation at 395 nm.

Preparation and Characterization of Organic Light Emitting Devices Using QD Dopant

2004 ◽  
Vol 449-452 ◽  
pp. 1021-1024 ◽  
Author(s):  
Jung Yohn Cho ◽  
Ho Jung Chang
Keyword(s):  
Luminous Efficiency ◽  
Host Material ◽  
Oled Device ◽  
Emission Layer ◽  
Maximum Brightness ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Organic Light ◽  
Organic Light Emitting Devices

Two types of the organic light-emitting devices (OLEDs) with different emission structures were prepared using Alq3 (aluminum tris 8-hydroxyquinoline) host material and quinacridone (QD) dopant at the emission layer. One is the OLED device with emission layer consisting of Alq3 host material doped with QD dopant ("codoped OLED"). The another one has a seperated QD dopant film in the Alq3 emission layer ("undoped OLED"). The maximum brightness of the codoped and undoped OLEDs were 3207 cd/m2 and 1570 cd/m2, respectively. The wavelength of the maximum emission peak in the undoped sample was 527 nm and shifted slightly toward longer wavelength with the value of 540 nm for the codoped OLED sample. The maximum luminous efficiency of the undoped OLED was about 1.4 lm/W and increased to 7.0 lm/W for the codoped sample.

Visible Luminescence of the InGaN/GaN Ultraviolet Light-emitting Diodes 365 nm

2017 ◽  
Vol 9 (5) ◽  
pp. 05031-1-05031-5 ◽  
Author(s):  
V. P. Veleschuk ◽  
◽  
A. I. Vlasenko ◽  
Z. K. Vlasenko ◽  
D. N. Khmil ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
Visible Luminescence ◽  
Ultraviolet Light Emitting Diodes

The mechanism of formation of 2,7-dimethyl-2,6-octadiene in the synthesis of 3-methylene-7-methyl-1,6-octadiene

1983 ◽  
Vol 48 (7) ◽  
pp. 1864-1866
Author(s):  
Jan Bartoň ◽  
Ivan Kmínek
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Alkali Metal ◽  
Chromatographic Analysis ◽  
Solid Phase ◽  
Reaction Pathway ◽  
Mechanism Of Formation ◽  
Gas Chromatographic Analysis ◽  
C Nmr ◽  
Visual Observations

2,7-Dimethyl-2,6-octadiene is formed in the catalytic solution for the dimerization of 2-methyl-1,3-butadiene to β-myrcene (3-methylene-7-methyl-1,6-octadiene), as revealed by mass spectrometry and 13C NMR spectroscopy. Visual observations together with the results of gas chromatographic analysis of the catalytic solution suggest that the formation of 2,7-dimethyl-2,6-octadiene is associated with the transition of the alkali metal (sodium) from the solid phase into the solution. A reaction pathway is suggested accounting for the formation of 2,7-dimethyl-2,6-octadiene in the system.

A New Dimeric Derivative of Ethoxyquin from Its Reaction with Alkylperoxy Radicals

1993 ◽  
Vol 58 (8) ◽  
pp. 1914-1918 ◽  
Author(s):  
Jaroslav Kříž ◽  
Luděk Taimr
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Peroxy Radicals ◽  
Methyl Group ◽  
Alkylperoxy Radicals ◽  
C Nmr

The structure of a new compound formed in the reaction of ethoxyquin with alkylperoxy radicals was resolved by 1H and 13C NMR spectroscopy (including COSY, NOESY, HHC RCT and SSLR INEPT techniques) and confirmed by mass spectrometry. The structure suggest participation of 4-methyl group of ethoxyquin in the deactivation of peroxy radicals. A mechanism of this reaction is proposed.

scholarly journals A Novel Thiosemicarbazide-Based Fluorescent Chemosensor for Hypochlorite in Near-Perfect Aqueous Solution and Zebrafish

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 65
Author(s):  
Minji Lee ◽  
Donghwan Choe ◽  
Soyoung Park ◽  
Hyeongjin Kim ◽  
Soomin Jeong ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reactive Oxygen Species ◽  
Aqueous Solution ◽  
Fluorescence Quenching ◽  
Limit Of Detection ◽  
Fluorescent Sensor ◽  
Ionization Mass ◽  
Oxygen Species ◽  
Marked Selectivity ◽  
Uv Visible

A novel thiosemicarbazide-based fluorescent sensor (AFC) was developed. It was successfully applied to detect hypochlorite (ClO−) with fluorescence quenching in bis-tris buffer. The limit of detection of AFC for ClO− was analyzed to be 58.7 μM. Importantly, AFC could be employed as an efficient and practical fluorescent sensor for ClO− in water sample and zebrafish. Moreover, AFC showed a marked selectivity to ClO− over varied competitive analytes with reactive oxygen species. The detection process of AFC to ClO− was illustrated by UV–visible and fluorescent spectroscopy and electrospray ionization–mass spectrometry (ESI–MS).

scholarly journals High-performance quasi-2D perovskite light-emitting diodes: from materials to devices

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Li Zhang ◽  
Changjiu Sun ◽  
Tingwei He ◽  
Yuanzhi Jiang ◽  
Junli Wei ◽  
...  
Keyword(s):  
Energy Transfer ◽  
High Performance ◽  
Light Emitting Diodes ◽  
Structural Characteristics ◽  
Quantum Yields ◽  
Research Directions ◽  
Light Emitting ◽  
Perovskite Materials ◽  
Quantum Confinement Effects ◽  
Semiconducting Properties

AbstractQuasi-two-dimensional (quasi-2D) perovskites have attracted extraordinary attention due to their superior semiconducting properties and have emerged as one of the most promising materials for next-generation light-emitting diodes (LEDs). The outstanding optical properties originate from their structural characteristics. In particular, the inherent quantum-well structure endows them with a large exciton binding energy due to the strong dielectric- and quantum-confinement effects; the corresponding energy transfer among different n-value species thus results in high photoluminescence quantum yields (PLQYs), particularly at low excitation intensities. The review herein presents an overview of the inherent properties of quasi-2D perovskite materials, the corresponding energy transfer and spectral tunability methodologies for thin films, as well as their application in high-performance LEDs. We then summarize the challenges and potential research directions towards developing high-performance and stable quasi-2D PeLEDs. The review thus provides a systematic and timely summary for the community to deepen the understanding of quasi-2D perovskite materials and resulting LED devices.

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