Article
Chemistry, Multidisciplinary
Shu-Jen Wang, Anton Kirch, Michael Sawatzki, Tim Achenbach, Hans Kleemann, Sebastian Reineke, Karl Leo
Summary: Conventional organic optoelectronic devices have low carrier mobility due to disorder. This study presents monolithic integrated triclinic crystal rubrene light-emitting diodes (LEDs) with engineered functional additives. The crystalline LEDs show superior charge transport, operational stability, and long-term stability. However, the crystalline phase reduces the overall performance compared to amorphous rubrene in terms of exciton dynamics and annihilation rates. The potential applications of rubrene and/or its derivatives crystalline films for improving the performance of organic and hybrid optoelectronic devices are discussed.
ADVANCED FUNCTIONAL MATERIALS
(2023)
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, 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
Biochemistry & Molecular Biology
Ren Sheng, Cong Chen, Erdong Zhang, Wencheng Zhao, Jihua Tang, Duxu Yan, Zhengze Li, Ping Chen
Summary: This study proposes a strategic design rule for interfacial exciplex hosts to overcome the negative effects of direct trapping recombination and systematically investigates exciton recombination behavior. As a result, highly efficient phosphorescent OLEDs with low driving voltages are achieved.
Article
Chemistry, Multidisciplinary
Chokchai Kaiyasuan, Vetiga Somjit, Bundet Boekfa, Daniel Packwood, Pongsakorn Chasing, Taweesak Sudyoadsuk, Kanokwan Kongpatpanich, Vinich Promarak
Summary: This study proposes the design of a new metal-organic framework (MOF) with enhanced hole mobility, and successfully applies it in organic light-emitting diodes (OLEDs), producing bright green light.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Multidisciplinary Sciences
Jin-Hoon Kim, Jin-Woo Park
Summary: An intrinsically stretchable organic light-emitting diode, made of highly stretchable constituent materials, is able to emit light under strains as large as 80%. It has a low turn-on voltage of 8 V and a maximum luminance of 4400 cd m(-2) from both the anode and cathode sides. The device can withstand repeated stretching cycles up to 200 times and shows improved light-emitting efficiency with small stretches up to 50%.
Review
Engineering, Electrical & Electronic
Kanchan Sharma, Bushra Abbas
Summary: Organic light emitting transistors (OLETs) have made progress in the field of optoelectronic devices, integrating the characteristics of electroluminescence from organic light emitting diodes (OLEDs) with the processes of organic field-effect transistors (OFETs). OLETs, as an upgraded form of OLEDs, have gained attention due to their architecture, flexibility, light weight, and low cost. This review focuses on the development of high-efficiency OLETs, considering different OLET structures and optimizations, and also compares them to OLEDs.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Chemistry, Physical
Murali Gedda, Despoina Gkeka, Mohamad Insan Nugraha, Alberto D. Scaccabarozzi, Emre Yengel, Jafar Khan, Lain Hamilton, Yuanbao Lin, Marielle Deconinck, Yana Vaynzof, Frederic Laquai, Donal D. C. Bradley, Thomas D. Anthopoulos
Summary: This study reports highly efficient green PeLEDs based on blends of low-dimensional hybrid perovskite and organic semiconductor, which achieve greatly enhanced performance characteristics through the use of self-assembled monolayers as hole-injecting layers.
ADVANCED ENERGY 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
Chemistry, Multidisciplinary
Xiangyu Fu, Yash Mehta, Yi-An Chen, Lei Lei, Liping Zhu, Nilesh Barange, Qi Dong, Shichen Yin, Juliana Mendes, Siliang He, Renuka Gogusetti, Chih-Hao Chang, Franky So
Summary: The study demonstrates highly directional and polarized light emission from LEDs by selectively diffracting the TE waveguide mode, showing potential for more efficient photonic applications.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jeong Yong Park, Seon Lee Kwak, Hea Jung Park, Do-Hoon Hwang
Summary: We synthesized a new polymer PICA for solution-processed OLEDs, with suitable energy levels for hole transport. PICA was photo-crosslinked with FPA as the photoinitiator, resulting in enhanced solvent resistance. OLED devices using PICA as the hole-transporting layer exhibited better performance than those using poly-TPD:FPA. This study demonstrates the potential application of photo-crosslinked PICA in solution-processed OLEDs.
Article
Optics
Zhaojun Li, Jixin Jiang, Yao Lu, Dandan Song, Bo Qiao, Suling Zhao, Zheng Xu
Summary: A new Pt(II)-complex named AT8809 was used as a dopant in the preparation of green phosphorescent light emitting diodes, leading to red shifts in the device spectra due to interactions between excitons and AT8809 aggregation luminescence.
JOURNAL OF LUMINESCENCE
(2022)
Article
Chemistry, Multidisciplinary
Yuhan Gao, Qin Xue, Guohua Xie
Summary: This study introduces a thermally activated delayed fluorescence (TADF) polymer into the emitting layer of quantum dot light emitting diodes (QLEDs) to simplify the device structure and promote fluorescence resonance energy transfer. By optimizing the host selection, the emission from the TADF polymer itself can be suppressed, significantly improving the color purity of QLEDs. The fabricated CdZnS/ZnS core/shell red QLEDs, without using any hole transport layer, achieved a maximum external quantum efficiency of 18.1%. The cascaded energy transfer in the ternary emitting layer provides a promising strategy for constructing highly efficient and simplified QLEDs.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Materials Science, Multidisciplinary
Chao Shi, Hong Huang, Qiuxia Li, Jingwen Yao, Cuicui Wu, Yibo Cao, Fangxiang Sun, Dongge Ma, Hong Yan, Chuluo Yang, Aihua Yuan
Summary: The study describes a novel strategy towards a series of charged ligand-based neutral iridium(III) complexes with adjustable color emission from blue-green to near-infrared. These complexes show excellent chemical and thermal stability, making them suitable for OLED devices with high external quantum efficiency, low efficiency roll-off, and turn-on voltage. This research provides new opportunities for optoelectronic applications of novel phosphorescent iridium(III) complex materials with tunable properties.
ADVANCED OPTICAL MATERIALS
(2021)
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, Physical
Chien-Chen Kuo, Ganesh D. Sharma, Fang-Chung Chen
Summary: This study demonstrates that the power conversion efficiency (PCE) of single-crystal solar cells can be improved by modifying the hole-transport layer (HTL). By blending a specific substance into the interfacial layer, the series resistance (Rs) can be reduced, resulting in a notable improvement in the performance of the solar cells. Stability tests suggest that the doping process has little effect on the reliability of the devices.
SURFACES AND INTERFACES
(2022)
Review
Nanoscience & Nanotechnology
Tzu-Yi Lee, Li -Yin Chen, Yu-Yun Lo, Sujith Sudheendran Swayamprabha, Amit Kumar, Yu-Ming Huang, Shih-Chen Chen, Hsiao-Wen Zan, Fang -Chung Chen, Ray-Hua Horng, Hao-Chung Kuo
Summary: Micro-light-emitting diodes (mu LEDs) are gaining significant attention in the display industry due to their exceptional optical and electrical characteristics. However, the high production cost and low external quantum efficiency (EQE) are major obstacles for their commercial usage. This article discusses the breakthroughs in mu LED technology, fabrication methods, optical/electrical characteristics, and challenges for display applications, offering potential solutions to address these challenges.
Article
Engineering, Chemical
Tzu-Hsueh Wu, Ganesh D. Sharma, Fang-Chung Chen
Summary: This article introduces a method of using TOPO treatment to passivate surface defects in single-crystal perovskite solar cells, thereby improving the photovoltaic performance and stability of the cells.
Article
Energy & Fuels
Hao-Yeu Tsai, Yung-Fang Yang, Hong-Sheng Jiang, Fang-Chung Chen
Summary: 2D perovskites with nearly vertically oriented Ruddlesden-Popper (RP) phases are grown using a vapor venting space-limited crystallization method, minimizing the impact of bulky side chains of the ammonium cations. Surface passivation is used to lower surface defects and improve power conversion efficiency (PCE), resulting in a PCE higher than 16%.
Article
Chemistry, Multidisciplinary
Tzu-Yi Lee, Tsau-Hua Hsieh, Wen-Chien Miao, Konthoujam James Singh, Yiming Li, Chang-Ching Tu, Fang-Chung Chen, Wen-Chung Lu, Hao-Chung Kuo
Summary: In this study, highly stable perovskite quantum dots (PQDs) coated with Al2O3 using atomic layer deposition (ALD) passivation technology were proposed. The passivation layer effectively protected the QDs from various conditions and exhibited excellent stability and reliability. By integrating with red phosphor, a white-light system with high data transmission rate was achieved.
Article
Chemistry, Physical
Mukhamed L. Keshtov, Dmitry Y. Godovsky, Ilya E. Ostapov, Vladimir G. Alekseev, Hemraj Dahiya, Rahul Singhal, Fang-Chung Chen, Ganesh D. Sharma
Summary: Researchers prepared a donor-acceptor conjugated polymer P(DTB-BDD) and achieved high power conversion efficiencies in solar cells by blending it with non-fullerene acceptors. By optimizing the weight ratios of the acceptors and keeping a constant amount of the donor, the performance of the solar cells can be further improved.
MOLECULAR SYSTEMS DESIGN & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Mukhamed L. Keshtov, Alexei R. Khokhlov, Dimitriy Y. Shikin, Vladimir Alekseev, Giriraj Chayal, Hemraj Dahiya, Manish Kumar Singh, Fang Chung Chen, Ganesh D. Sharma
Summary: A new medium bandgap non-fullerene small-molecule acceptor (IDT-TC) was designed and compared with IDT-IC acceptor in terms of optical and electrochemical properties. IDT-TC exhibited higher crystallinity and electron mobility compared to IDT-IC. In polymer solar cells, using IDT-TC as the acceptor and P as the donor, achieved a higher power conversion efficiency.
Article
Chemistry, Multidisciplinary
Gajendra Suthar, Yu-Tang Hsiao, Kuen-Wei Tsai, Chuang-Yi Liao, Chih-Wei Chu, Yi-Ming Chang, Fang-Chung Chen
Summary: The impact of non-fullerene acceptor Y6-Se-HD on the performance of photomultiplication-type organic photodetectors is investigated. The results show that Y6-Se-HD can enhance the performance of the photodetectors by facilitating charge trapping and preventing charge recombination. The research highlights the importance of morphological effects on the performance of photomultiplication-type organic photodetectors.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Physics, Applied
Gautham Kumar, Fang-Chung Chen
Summary: Organic photovoltaics (OPVs) have the potential to become a new generation of energy sources due to their unique properties and high power conversion efficiencies under indoor and low-level lighting conditions. This article reviews recent progress in OPV devices for special applications such as the Internet of Things, wearable electronics, and sensors. It discusses the fundamental principles of OPVs, preparation and design of photoactive layers for indoor applications, the importance of interlayers, efforts to improve efficiencies using plasmonic nanostructures, and progress in large-area devices and modules for indoor applications.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Tzu-Yi Lee, Wen-Chien Miao, Yu-Ying Hung, Yi-Hong Bai, Pei-Tien Chen, Wei-Ta Huang, Kuan-An Chen, Chien-Chung Lin, Fang-Chung Chen, Yu-Heng Hong, Hao-Chung Kuo
Summary: This study proposes a novel structural design that combines blue and quantum well (QW)-intermixing ultraviolet (UV)-hybrid μ-LEDs to achieve high color-conversion efficiency (CCE). Through simulations, various combinations of QD and TiO2 concentrations and thickness variations are examined for their impact on photoluminescence efficiency (PLQY). The resulting high-efficiency color-conversion layer (CCL) saves time and material costs and enhances light absorption and illumination uniformity. The research also introduces a passivation protection layer and a modified distributed Bragg reflector (DBR) to improve device reliability and achieve high CCE values.
Article
Crystallography
Tzu-Yi Lee, Wei-Ta Huang, Jo-Hsiang Chen, Wei-Bo Liu, Shu-Wei Chang, Fang-Chung Chen, Hao-Chung Kuo
Summary: This study focuses on the innovation of mini light-emitting diode (mini-LED) backlight module designs. By optimizing the Mini-LED structure and utilizing optical simulation software and reinforcement learning algorithms, the illumination uniformity was improved, achieving impressive results.
Article
Nanoscience & Nanotechnology
Fu-He Hsiao, Tzu-Yi Lee, Wen-Chien Miao, Yi-Hua Pai, Daisuke Iida, Chun-Liang Lin, Fang-Chung Chen, Chi-Wai Chow, Chien-Chung Lin, Ray-Hua Horng, Jr-Hau He, Kazuhiro Ohkawa, Yu-Heng Hong, Chiao-Yun Chang, Hao-Chung Kuo
Summary: This study demonstrates the potential of InGaN-based red micro-LEDs with a single quantum well (SQW) structure for visible light communication applications. The SQW sample shows better crystal quality, with high-purity emission, narrower full width at half maximum, and higher internal quantum efficiency compared to InGaN red micro-LEDs with a double quantum wells (DQWs) structure. The SQW device exhibits higher maximum external quantum efficiency (5.95%) and experiences less blueshift with increasing current density compared to the DQWs device. Furthermore, the SQW device has a superior modulation bandwidth (424 MHz) and a data transmission rate of 800 Mbit/s at an injection current density of 2000 A/cm(2). These results indicate that InGaN-based SQW red micro-LEDs hold great promise for full-color micro-display and visible light communication applications.
Review
Materials Science, Multidisciplinary
Prateek Malhotra, Kanupriya Khandelwal, Subhayan Biswas, Fang-Chung Chen, Ganesh D. Sharma
Summary: The development and challenges of machine learning in organic solar cells are discussed. The flexibility of organic semiconductors offers new possibilities for discovering battery materials. Some progress has been made, and impactful techniques for extracting useful information have been identified. However, there are still limitations in the machine learning workflow.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Cheng-Han Sung, Shi-Da Huang, Gautham Kumar, Wen-Chi Lin, Chien-Chung Lin, Hao-Chung Kuo, Fang-Chung Chen
Summary: In this study, high photoluminescence quantum yield organic-inorganic hybrid perovskite quantum dots (PeQDs) were synthesized for light-emitting applications. The PeQDs, when mixed with polydimethylsiloxane, acted as a color-conversion layer (CCL) for quantum-dot light emitting diodes (LEDs) and achieved high power efficiency. By blending the PeQDs with polyvinylcinnamate, photopatternable thin films were formulated and patterned using UV light. The resulting perovskite quantum dot-polymer nanocomposites (PQD-PNCs) showed higher PLQY and stability, suggesting their potential as effective CCLs for future micro-LEDs.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Review
Chemistry, Multidisciplinary
Yu-Ming Huang, Konthoujam James Singh, Tsou-Hwa Hsieh, Catherine Langpoklakpam, Tzu-Yi Lee, Chien-Chung Lin, Yiming Li, Fang-Chung Chen, Shih-Chen Chen, Hao-Chung Kuo, Jr-Hau He
Summary: Quantum dots (QDs) offer unparalleled advantages in advanced display technologies due to their excellent photoluminescence and wide color coverage. Understanding how QD properties affect LED display performance is crucial for developing energy-efficient display devices. Research on stability issues and passivation methods of QDs is essential for accelerating the commercialization of QD-based LED technologies.
