Hybrid White Quantum Dot-Organic Light-Emitting Diodes with Highly Stable CIEx,y Coordinates by Introduction of n-Type Modulation and Multi-Stacked Hole Transporting Layer

2021 ◽  
Author(s):  
Hakjun Lee ◽  
Seung-Won Song ◽  
Kyo Min Hwang ◽  
Ki Ju Kim ◽  
Heesun Yang ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Light Emitting Diode ◽  
Organic Light Emitting Diodes ◽  
Device Structure ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Device Architecture ◽  
Organic Light ◽  
Hole Transporting ◽  
Novel Concept

Extremely stable white emission out of a hybrid white quantum dot-organic light-emitting diode (WQD-OLED) was achieved by developing a novel concept of device architecture. The new inverted device structure employs...

Effect of Double Hole-Transporting Structure on Color Purity of Blue Organic Light-Emitting Diodes (BOLED)

2013 ◽  
Vol 311 ◽  
pp. 424-429
Author(s):  
Kan Lin Chen ◽  
Chien Jung Huang ◽  
Zong Jin Wu ◽  
Chih Chieh Kang ◽  
Wen Ray Chen ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Organic Light Emitting Diodes ◽  
Blue Color ◽  
Color Purity ◽  
Television System ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Hole Transporting ◽  
The Right

A blue organic light-emitting diode (OLED) with a double hole-transporting (DHT) structure has been developed. The blue color purity was improved by modulation the thickness of CBP layer. When the thicknesses of left CBP and right CBP are respectively 8 nm and 2 nm, the more pure blue coordinates are (0.155, 0.079), which are very close to the blue coordinates of the national television system committee (NTSC) standard (0.14, 0.08). Furthermore the current density, brightness and the luminous efficiency of device with the left CBP of 8 nm and the right CBP of 2 nm are respectively 144.7 mA/cm2, 1065 cd/m2 and 0.93 cd/A.

High Performance Non-Doped Green Organic Light Emitting Diode via Delayed Fluorescence

2021 ◽  
Author(s):  
Bahadur Sk ◽  
Vasudevan Thangaraji ◽  
Nisha Yadav ◽  
Gyana Prakash Nanda ◽  
SANNIBHA DAS ◽  
...  
Keyword(s):  
High Performance ◽  
Light Emitting Diode ◽  
Delayed Fluorescence ◽  
Device Fabrication ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Hole Transporting ◽  
Anthracene Derivatives

Non-doped, delayed fluorescence organic light-emitting diodes (OLEDs) provide a route to high performance devices and simplified device fabrication. Here, two ambipolar anthracene derivatives containing a hole-transporting di-ptolylamine or a carbazole...

scholarly journals Unravelling the electron injection/transport mechanism in organic light-emitting diodes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Tsubasa Sasaki ◽  
Munehiro Hasegawa ◽  
Kaito Inagaki ◽  
Hirokazu Ito ◽  
Kazuma Suzuki ◽  
...  
Keyword(s):  
Work Function ◽  
Transport Mechanism ◽  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Electron Injection ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Materials Used

AbstractAlthough significant progress has been made in the development of light-emitting materials for organic light-emitting diodes along with the elucidation of emission mechanisms, the electron injection/transport mechanism remains unclear, and the materials used for electron injection/transport have been basically unchanged for more than 20 years. Here, we unravelled the electron injection/transport mechanism by tuning the work function near the cathode to about 2.0 eV using a superbase. This extremely low-work function cathode allows direct electron injection into various materials, and it was found that organic materials can transport electrons independently of their molecular structure. On the basis of these findings, we have realised a simply structured blue organic light-emitting diode with an operational lifetime of more than 1,000,000 hours. Unravelling the electron injection/transport mechanism, as reported in this paper, not only greatly increases the choice of materials to be used for devices, but also allows simple device structures.

Influence of hole transporting material on device performance in organic light-emitting diode

2000 ◽  
Vol 363 (1-2) ◽  
pp. 290-293 ◽  
Author(s):  
Shizuo Tokito ◽  
Koji Noda ◽  
Kou Shimada ◽  
Shin-ichiro Inoue ◽  
Makoto Kimura ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Device Performance ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Hole Transporting ◽  
Hole Transporting Material

Cohosts with efficient host-to-emitter energy transfer for stable blue phosphorescent organic light-emitting diodes

2021 ◽  
Author(s):  
Soo-Ghang Ihn ◽  
Eun Suk Kwon ◽  
Yongsik Jung ◽  
Jong Soo Kim ◽  
Sungho Nam ◽  
...  
Keyword(s):  
Energy Transfer ◽  
High Performance ◽  
Light Emitting Diode ◽  
Organic Light Emitting Diodes ◽  
Operating Voltage ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Low Efficiency ◽  
Blue Phosphorescent

We present a high-performance blue phosphorescent organic light-emitting diode exhibiting a low operating voltage (4.1 V), high external quantum efficiency (23.4%, at 500 cd m-2) with a low efficiency roll-off...

High efficiency above 20% in polymeric thermally activated delayed fluorescent organic light-emitting diodes by a host embedded backbone structure

2019 ◽  
Vol 10 (35) ◽  
pp. 4872-4878 ◽  
Author(s):  
Yun Hwan Park ◽  
Ho Jin Jang ◽  
Jun Yeob Lee
Keyword(s):  
High Efficiency ◽  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Thermally Activated ◽  
Highly Efficient ◽  
Organic Light ◽  
Backbone Structure

A highly efficient polymeric thermally activated delayed fluorescent (TADF) organic light-emitting diode was developed by synthesizing a copolymer with 9-vinylcarbazole (VCz) and TADF repeating units.

Covalent Functionalized Conjugated Dendrimers for Organic Light Emitting Diodes: Synthesis, Characterization, and the Deep Blue Electroluminescence

2011 ◽  
Vol 64 (2) ◽  
pp. 160 ◽  
Author(s):  
Yan Zhou ◽  
Lin Ding ◽  
Li-Ming Xiang ◽  
Jian Pei
Keyword(s):  
Light Emitting Diode ◽  
Photophysical Properties ◽  
Single Layer ◽  
Blue Colour ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Deep Blue ◽  
Organic Light ◽  
Hole Transporting ◽  
Cie Chromaticity

Two deep blue-emitting dendrimers 11 and 12 with carbazole containing dendrons were developed in this contribution. The carbazole-containing units were introduced to tune the charge-transporting property of the desired dendrimers. The investigation of photophysical properties, electrochemical, and electroluminescence properties demonstrated that the balance between electron and hole transporting was achieved from both dendrimers. The preliminary organic light-emitting diode (OLED) fabrication achieved a pure blue colour with stable CIE chromaticity coordinates (X: 0.15–0.16, Y: 0.09–0.10) for 11 and 12. Single layer deep blue emitting diode devices with higher efficiency are achieved without the colour changing. The investigation of OLED performance indicates that dendrimers 11 and 12 are promising light-emitting materials with pure blue colour and good colour stability for OLEDs.

A life estimation model applied to organic light-emitting diodes

2018 ◽  
Vol 51 (5) ◽  
pp. 764-773
Author(s):  
JP Zhang ◽  
Y Zong ◽  
Y Meng ◽  
WG Pan ◽  
JS Tang
Keyword(s):  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Decay Data ◽  
Light Emitting Devices ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Extrapolation Model ◽  
Accelerated Life

For predicting life for light-emitting devices quickly and accurately, a novel life prediction model, namely an extrapolation model of accelerated life and stress, has been proposed. In this model, a Weibull function is employed to fit luminance decay data under multiple groups of accelerated stresses, and the corresponding accelerated life is obtained. By determination coefficients and root mean square errors, a power function is determined as an extrapolated function to describe the relationship between accelerated life and stress and the life of the light-emitting devices. For organic light-emitting diodes, three groups of constant-stress accelerated degradation tests were conducted by increasing current stress. An extrapolation model of accelerated life and stress was applied to process the collected luminance decay data and was evaluated by a careful comparison with organic light-emitting diode life. The results indicate that the self-designed experimental scheme for organic light-emitting diode is feasible and versatile; the predicted life is 17,113 hours, which is close to the service life derived from user feedback, and the relative error is only 2.2%. This shows that the extrapolation model of accelerated life and stress has high precision; the model reveals the expected law of luminance changing with time and intuitively depicts the life characteristics under accelerated stresses without conventional life tests. This will pave the way for a new method to predict and evaluate the life of modern light-emitting devices.

Carbon Quantum Dot as Electron Transporting Layer in Organic Light Emitting Diode

2019 ◽  
Vol 4 (25) ◽  
pp. 7450-7454 ◽  
Author(s):  
Md. Bayazeed Alam ◽  
Kanchan Yadav ◽  
Devyani Shukla ◽  
Ritu Srivastava ◽  
Jayeeta Lahiri ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Carbon Quantum Dot ◽  
Organic Light ◽  
Electron Transporting Layer
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