Article
Engineering, Environmental
Ki Ju Kim, Hakjun Lee, Sunwoo Kang, Taekyung Kim
Summary: A novel device architecture with an Ir-complex intermediate energy carrier (IEC) was proposed to create multiple energy transfer channels, leading to an unprecedentedly long lifetime in blue phosphorescent organic light-emitting diodes (PhOLEDs).
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Matthias Diethelm, Andrius Devizis, Wei-Hsu Hu, Tao Zhang, Roman Furrer, Camilla Vael, Sandra Jenatsch, Frank Nueesch, Roland Hany
Summary: The study identified that charge traps in semiconducting polymers present important intrinsic performance limitations for PLECs, similar to those for PLEDs.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Natsuo Nagamura, Hisahiro Sasabe, Hiroki Sato, Nozomi Ito, Shoki Abe, Yoshihito Sukegawa, Daisuke Yokoyama, Hironori Kaji, Junji Kido
Summary: Using a tailored high triplet energy hole transport layer is an effective way to improve the efficiency and lifetime of organic light-emitting devices. In this study, two HTL materials were developed and showed excellent performance in terms of external quantum efficiency and operational lifetime in green phosphorescent OLEDs.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Computer Science, Information Systems
Dan Chen, Taoran Liu, Yuhua Zuo, Chuanbo Li, Jun Zheng, Zhi Liu, Baoyu Liu, Buwen Cheng
Summary: This study investigates the effect of strontium (Sr) doping on quasi-2D perovskite layers to improve their film morphology and luminescence property, thus enhancing the photoelectric performance of PeLEDs. The results show that the Sr-doped quasi-2D perovskite layers exhibit higher photoluminescence intensity and luminance, as well as excellent stability and performance.
TSINGHUA SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Zhiheng Wang, Xiaoxian Song, Qishen Chen, Jie Liang, Zhengqian Tu, Chenhui Wang, Zuolun Zhang, Hai Bi, Yue Wang
Summary: Exciplex-forming cohosts with different recombination mechanisms, particularly trimolecular Langevin recombination, exhibit higher luminance lifetimes and better resistance to deterioration compared to trap-assisted recombination cohosts. Additionally, controlling exciton management in the recombination region can suppress luminous decline and undesirable exciton-exciton annihilations.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Sangdong Kim, Jae-Min Kim, Jongwon Choi, Myungsun Sim, Yasushi Koishikawa, Yong-Suk Cho, Sungjun Kim, Seung-Yeon Kwak, Aram Jeon, Ohyun Kwon, Duck-Hyung Lee, Jun Yeob Lee, Byungki Choi
Summary: The horizontal orientation of the transition dipole moment plays a crucial role in improving the external quantum efficiency (EQE) of organic light-emitting diodes. In this study, red-emitting heteroleptic iridium (III) complexes with a high horizontal ratio of emitting dipole orientation (EDO) and photoluminescence quantum yield (PLQY) were reported, leading to enhanced device performance and longer operational lifetime. This approach opens up possibilities for further development of red-emitting iridium complexes to achieve higher device efficiencies.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Shiyun Lei, Yuanyuan Xiao, Kanglin Yu, Biao Xiao, Ming Wan, Liyong Zou, Qingliang You, Renqiang Yang
Summary: This study investigates the hole injection mechanism in quantum dot light-emitting diodes (QLEDs) through a combination of experiments and simulations. It reveals that applied bias reduces the barrier height, facilitating hole injection and confining electrons within the quantum dots. The research also demonstrates that thermally assisted tunneling is the predominant pathway for hole injection. This study is significant for understanding the hole injection mechanism in QLEDs.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Hui-Hui Jiang, Jing Xiao, Hai-Tian Huang, Di Wu, Ru-Xin Song, Rong Xu, Xu Gao, Jian-Long Xu, Steffen Duhm, Li-Feng Chi, Sui-Dong Wang
Summary: Appropriate Ar plasma treatment on ITO surface can induce small-sized and dense injection hotspots, achieving efficient electron injection and playing a critical role in organic electronic devices.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Yujie Han, Yang Shen, Kongchao Shen, Zhenhuang Su, Yanqing Li, Fei Song, Xingyu Gao, Jian-Xin Tang
Summary: This study investigates the influence of the hole transport layer on charge transport and recombination processes in PeLEDs through impedance spectroscopy. The results show that rational interfacial energy level alignment can improve radiative recombination efficiency and enhance device performance.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Xinyu Shen, Hua Wu, Xiaoyu Zhang, Meili Xu, Junhua Hu, Jinyang Zhu, Bin Dong, William W. Yu, Xue Bai
Summary: The all-solution process for inorganic perovskite nanocrystals (PNCs) LEDs shows great potential for new-generation illumination and displays, but the challenge lies in the injection barriers and charge injection imbalance. The introduction of CBP into the hole transport layer (HTL) efficiently modulates the charge carrier mobility and energy level, resulting in barrier-free charge injection and optimal performance for solution-processed PNC LEDs. The luminance of red LEDs reaches 2990 cd m(-2) and the external quantum efficiency achieves 8.1%, with improved turn-on voltage and roll-off due to more balanced charge injection.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Polymer Science
Zong-Liang Tseng, Shih-Hung Lin, Jian-Fu Tang, Yu-Ching Huang, Hsiang-Chih Cheng, Wei-Lun Huang, Yi-Ting Lee, Lung-Chien Chen
Summary: This study investigates the performance of red CsPbI3-based all-inorganic perovskite quantum-dot light-emitting diodes using different hole transporting layers (HTLs), with VB-FNPD showing the best external quantum efficiency. Improvements in the polymerization of VB-FNPD lead to enhanced device performance.
Article
Chemistry, Physical
Kiun Cheong, Unhyeok Jo, Wan Pyo Hong, Jun Yeob Lee
Summary: A blue tetradentate Pt(II) complex named Pt-tmCyCz is developed by introducing a cycloalkyl unit fused to carbazole to improve the rigidity and bulkiness of the complex. The complex exhibits high external quantum efficiency, narrow full width at half maximum, and stable spectrum in OLEDs.
Article
Optics
Shuaibing Li, Liang Zhou, Qi Zhu, Ruixia Wu, Kai Chen, Zhenzhen Li, Hongjie Zhang
Summary: Novel blue and white organic light-emitting diodes (OLEDs) were designed using FK306 as a sensitizer, which acts as an electron trapper in the electron transport layer, enhancing carrier recombination probability and suppressing exciton annihilation. This results in improved device performance with low turn-on voltages and high efficiencies.
JOURNAL OF LUMINESCENCE
(2021)
Article
Materials Science, Multidisciplinary
Yungui Li, Naresh B. Kotadiya, Bas van der Zee, Paul W. M. Blom, Gert-Jan A. H. Wetzelaer
Summary: This study presents a numerical model to simulate the optical outcoupling efficiency of OLEDs with a broad recombination zone, demonstrating that single-layer OLEDs can achieve high outcoupling efficiency similar to multilayer OLEDs. The simulations are validated with experiments on OLEDs of different thickness, showing potential for efficient, stable, and simplified OLED designs.
ADVANCED OPTICAL MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Amit Kumar Mondal, Xin Pan, Ohyun Kwon, Zeev Valy Vardeny
Summary: Understanding the stability and degradation of OLEDs under working conditions is essential for developing more effective and high-performance OLEDs. However, there is a lack of adequate in situ noninvasive methods for studying degradation processes. In this study, the degradation of Alq3-based OLEDs was analyzed through the investigation of the MEL(B) response measured at room temperature. The analysis provides insights into the spin-dependent phenomena controlling the recombination of e-h polaron pairs in the device and reveals changes in polaron lifetime, dispersive parameter, and lifetime distribution function during device degradation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Ji Han Kim, Jun Yeob Lee
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Sung Moo Kim, Ju Hui Yun, Sung Yong Byeon, Sang Kyu Jeon, Jun Yeob Lee
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Hee Un Kim, Jae-Ho Jang, Hea Jung Park, Jun Yeob Lee, Do-Hoon Hwang
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
(2017)
Article
Optics
Chang-Mo Kang, Duk-Jo Kong, Jae-Phil Shim, Sanghyeon Kim, Sang-Bae Choi, Jun-Yeob Lee, Jung-Hong Min, Dong-Ju Seo, Soo-Young Choi, Dong-Seon Lee
Article
Materials Science, Multidisciplinary
Wook Song, Jun Yeob Lee
ORGANIC ELECTRONICS
(2017)
Article
Materials Science, Multidisciplinary
Jeong Min Choi, Ji Han Kim, Yu Jin Kang, Jun Yeob Lee
ORGANIC ELECTRONICS
(2017)
Article
Materials Science, Multidisciplinary
Jeong Min Choi, Woochul Lee, Kong Kyeom Kim, Jun Yeob Lee
ORGANIC ELECTRONICS
(2017)
Article
Materials Science, Multidisciplinary
Wook Song, Taekyung Kim, Yoonkyoo Lee, Jun Yeob Lee
ORGANIC ELECTRONICS
(2017)
Article
Materials Science, Multidisciplinary
Hyeong Min Kim, Jeong Min Choi, Jun Yeob Lee
ORGANIC ELECTRONICS
(2017)
Article
Chemistry, Applied
Kiun Cheong, Seung Chan Kim, Jun Yeob Lee
Summary: This study explores the potential of using o-carborane as a new acceptor in designing donor-acceptor (D-A) type thermally activated delayed fluorescence (TADF) materials. The designed D-A type TADF emitter exhibits deep red emission as proven by delayed fluorescence and electroluminescence analysis. The maximum external quantum efficiency of the devices is found to be 5.2% in the doped device and 2.1% in the non-doped device.
Article
Chemistry, Applied
Ji Han Kim, Minsik Eum, Tae Hyung Kim, Jun Yeob Lee
Article
Chemistry, Applied
Ju Hui Yun, Jun Yeob Lee
Article
Chemistry, Applied
Jeong Min Choi, Dong Ryun Lee, Jun Yeob Lee
Article
Nanoscience & Nanotechnology
Sung Yong Byeon, Ji Han Kim, Jun Yeob Lee
ACS APPLIED MATERIALS & INTERFACES
(2017)
Article
Chemistry, Multidisciplinary
Yirang Im, Seong Yong Byun, Ji Han Kim, Dong Ryun Lee, Chan Seok Oh, Kyoung Soo Yook, Jun Yeob Lee
ADVANCED FUNCTIONAL MATERIALS
(2017)