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%.
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
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
Materials Science, Multidisciplinary
Wei Chen, Chuan Xu, Lingqing Kong, Xiang-Yang Liu, Xingye Zhang, Naibo Lin, Xinhua Ouyang
Summary: This study reports the use of silk fibroin (SF) as a flexible OLED substrate to improve device performance by enhancing light extraction efficiency (LEE). SF-based flexible OLED outperforms the reference device in terms of turn-on voltage, peak brightness, and LEE. The improved performance can be attributed to the low refractive index of SF, its lower surface roughness, and more matched energy levels compared to other substrates. Additionally, a molecular dipole layer formed between the interface of indium tin oxide (ITO) and SF effectively changes the ITO work function, reducing the potential barrier height for hole transfer.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Clement Brouillac, Fan-Cheng Kong, Joelle Rault-Berthelot, Cassandre Quinton, Zuo-Quan Jiang, Cyril Poriel
Summary: Designing deep-blue fluorophores with a low CIEy is crucial for OLED technology, whether for display applications or new applications like antibacterial light sources. This study reports the synthesis, physico-chemical properties, and application of two deep-blue emitters in an OLED. The emitters demonstrated high device performance with suitable CIE coordinates, and one emitter showed a deep-blue emission with an EQE of 1.7% and a V-on of 4 V, fitting the NTSC and EBU standards.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Chemistry, Physical
Wenwen Wu, Yue Liu, Xinping Zhang
Summary: Researchers have developed a large-area array of nanoscale organic light-emitting diodes (OLEDs) that produce amplified emission with a selected spectrum in a narrow band. These OLEDs share a common active layer that acts as a waveguide and gain channel for light-emitting signals. The periodic structure of the array allows for diffraction and confinement of the electroluminescence signal, resulting in strong spectral selectivity and amplification.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Yang Li, Dejiang Zhao, Wei Huang, Zhiqiang Jiao, Lu Wang, Qingyu Huang, Peng Wang, Mengna Sun, Guangcai Yuan
Summary: An inverted red quantum dot light-emitting diode (QLED) with an organic emitting layer (EML) achieved peak current efficiency (CE) and external quantum efficiency (EQE) of 25.63 cd/A and 23.20%, respectively. The organic EML acted as an exciton harvester, capturing leaked electrons and injected holes to enhance the emission of quantum dots. Additionally, the insertion of the organic EML improved hole injection and balanced electron injection in the device, leading to a 2-fold improvement in CE and EQE compared to the control device, along with a better operational lifetime.
Article
Chemistry, Multidisciplinary
Liuqing Yang, Xuefei Li, Qingqing Yang, Shumeng Wang, Hongkun Tian, Junqiao Ding, Lixiang Wang
Summary: High-performance red quantum dot light-emitting diodes (QLEDs) with organic electron transporting layer (ETL) based on nitrogen heterocycle-containing compounds show record-high external quantum efficiency by tuning the energy levels to facilitate electron injection and achieving restored charge balance, indicating great potential of organic ETL towards efficient QLEDs.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Ki Chang Kwon, Tae Hyung Lee, Seokhoon Choi, Kyoung Soon Choi, Seung O. Gim, Sa-Rang Bae, Jong-Lam Lee, Ho Won Jang, Soo Young Kim
Summary: This study presents a simple method for synthesizing alloyed transition metal disulfides (TMD) thin films and their application as hole transport layers in OLEDs. The physical and chemical properties of the alloyed TMD layers can be controlled by varying precursor concentrations. The device performance of OLEDs based on alloyed TMD layers is comparable to conventional PEDOT:PSS, and device stability in air is significantly improved.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Linyu Cao, Zhi-Qiang Zhu, Kody Klimes, Jian Li
Summary: The tetradentate Pd(II) complexes exhibit promise in efficient and stable OLEDs, with slight changes in ligand structure being able to modify transport capabilities and enhance device lifetime performance.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jaber Saghaei, Steven M. Russell, Hui Jin, Paul L. Burn, Almantas Pivrikas, Paul E. Shaw
Summary: This study investigates the impact of annealing and phase separation on the performance of solution-processed OLEDs, highlighting the improved performance of devices with a low dendrimer concentration in the emissive layer following annealing. The external quantum efficiency of the OLEDs is found to be higher than expected due to different pathways of exciton formation under photoexcitation and charge injection.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Qianqian Wu, Fan Cao, Sheng Wang, Yimin Wang, Zhongjiang Sun, Jingwen Feng, Yang Liu, Lin Wang, Qiang Cao, Yunguo Li, Bin Wei, Wai-Yeung Wong, Xuyong Yang
Summary: A quasi-shell-growth strategy was reported to synthesize highly luminescent green InP/ZnSe/ZnS quantum dots, in which zinc and selenium monomers were added at the initial nucleation stage of InP cores to form a quasi-ZnSe shell instead of a bulk ZnSe shell. This strategy greatly improved the electroluminescence performance of green InP quantum dots.
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
Nanoscience & Nanotechnology
Heather F. Higginbotham, Masato Okazaki, Piotr de Silva, Satoshi Minakata, Youhei Takeda, Przemyslaw Data
Summary: This research introduces a new method to design heavy-atom-free organic room temperature phosphorescence emitters, enabling tailored emission properties and switching between thermally activated delayed fluorescence and room temperature phosphorescence emission channels. Furthermore, an efficient and heavy-atom-free room temperature phosphorescence organic light-emitting diode using the developed emitter has been realized.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Review
Chemistry, Multidisciplinary
Zhihong Sun, Aaqib Khurshid, Muhammad Sohail, Weidong Qiu, Derong Cao, Shi-Jian Su
Summary: This review summarizes the recent progress on the design and constructions of dye encapsulated luminescent MOFs phosphors, highlighting different strategies where white light emitting phosphors were obtained by combining fluorescent dyes with metal ions and linkers.
Article
Materials Science, Multidisciplinary
Eunice Y. Paik, Long Zhang, Shaocong Hou, Haonan Zhao, Yu-Hsun Chou, Stephen R. Forrest, Hui Deng
Summary: This study presents a method to assemble high quality-factor microcavities for van der Waals materials using high reflectance top mirrors. The method can be generalized to other photonic structures and will facilitate research using van der Waals materials.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Haonan Zhao, Jongchan Kim, Kan Ding, Mina Jung, Yongxi Li, Harald Ade, Jun Yeob Lee, Stephen R. Forrest
Summary: By incorporating a sterically bulky, electron-transporting host material into a conventional single host-guest emissive layer, the phase separation of the host matrix can be suppressed, leading to improved efficiency and operational lifetime of deep-blue phosphorescent organic light-emitting diodes (PHOLEDs). This bulky host allows for homogeneous mixing of the emissive layer molecules while preventing single host aggregation and nonradiative recombination. The controlled amorphous phase morphology of the mixed-host device reduces nonradiative exciton decay and enhances external quantum efficiency by 120 +/- 6% compared to a similar single-host device. Additionally, the mixed host facilitates the conduction of both charge carriers, reducing the probability of exciton annihilation and doubling the operational lifetime of deep-blue PHOLEDs.
ADVANCED MATERIALS
(2023)
Article
Automation & Control Systems
Zhiyi Chen, Boning Qu, Baoyang Jiang, Stephen R. Forrest, Jun Ni
Summary: Tension control is critical for maintaining good product quality in roll-to-roll (R2R) production systems. This study proposes a robust linear parameter-varying model predictive control (LPV-MPC) scheme to enhance tension tracking performance in a pilot R2R system. By separately handling disturbances caused by model uncertainties and dynamics changes, the controller achieves fast transient response and offset-free tension tracking.
Article
Multidisciplinary Sciences
Yan Li, Chengyu Zou, Chen Chen, Sixuan Li, Ziyu Zhu, Qiuyue Fan, Rui Pang, Fengshi Li, Zengai Chen, Zhenghong Wang, Weifeng Yu, Junying Yuan, Peiying Li
Summary: This study demonstrates that macrophage migration inhibitory factor (MIF) promotes endothelial cell (EC) death under inflammatory conditions, thus contributing to blood-brain barrier disruption.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Nanoscience & Nanotechnology
Claire Arneson, Xinjing Huang, Stephen R. Forrest
Summary: This study demonstrates a method for achieving tunable white light through the side-by-side positioning of monochromatic blue and yellow phosphorescent OLED stripes using a high-resolution mechanical peel-off patterning method. The results show a peak luminous power efficiency of 17.1 lm W-1 and an external quantum efficiency of 11.8%, as well as the ability to adjust the color temperature and color rendering index of the light source. The peel-off technique used in this method ensures a comparable device lifetime to conventionally patterned devices.
Review
Nanoscience & Nanotechnology
Yongxi Li, Xinjing Huang, Hafiz K. M. Sheriff Jr, Stephen R. Forrest
Summary: The narrow and intense absorption spectra of organic materials offer the possibility to develop efficient organic photovoltaic devices that are different from other solar cell technologies. By selectively absorbing light in specific ranges, these materials can be used for power-generating windows that are semitransparent in the visible range but absorb strongly in the ultraviolet and infrared regions, providing a sustainable solution for clean energy generation.
NATURE REVIEWS MATERIALS
(2023)
Article
Multidisciplinary Sciences
Yongxi Li, Xinjing Huang, Austin R. Mencke, Sunil Kumar Kandappa, Tonghui Wang, Kan Ding, Zuo-Quan Jiang, Aram Amassian, Liang-Sheng Liao, Mark E. Thompson, Stephen R. Forrest Abe
Summary: In order to improve the performance and lifetime of organic photovoltaic devices, precise control over the purity, composition, and structure of organic semiconductors is necessary. Ternary-blend organic photovoltaics have shown promise in improving solar spectral coverage and reducing energy losses. However, the blending process compromises the purity of the ternary blend, leading to impurities that affect device reproducibility and long-term reliability.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Multidisciplinary Sciences
Qiuyang Li, Adam Alfrey, Jiaqi Hu, Nathanial Lydick, Eunice Paik, Bin Liu, Haiping Sun, Yang Lu, Ruoyu Wang, Stephen Forrest, Hui Deng
Summary: A method based on 1-dodecanol encapsulation and gold-tape-assisted exfoliation is developed for the synthesis of large-area and high-quality transition metal dichalcogenide (TMD) monolayers. The encapsulated monolayers show uniform exciton energy, linewidth, and quantum yield over the whole area, and can be integrated with photonic crystal cavities to enhance light-matter coupling.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Boning Qu, Zhiyi Chen, Lucas Lahann, Stephen R. Forrest
Summary: White organic light emitting devices (WOLEDs) have advantages as solid state lighting sources, offering high energy efficiency, superior color quality, and a flexible, thin profile. Recent advances suggest that mass production of WOLED panels is approaching. This research estimates the cost of white WOLED panel production and predicts that with incremental costs reduction and improved luminance, WOLED lighting can be more affordable and suitable for various premium lighting applications.
Article
Physics, Applied
Jihun Lim, Stephen R. Forrest
Summary: Air-bridge thermophotovoltaic (ABTPV) devices achieve nearly 99% utilization of out-of-band (OOB) photons. The thermodynamic limit for single junction ABTPVs is determined to be 55.5% at an emitter temperature of 1400 K, compared to the reported efficiency of 32%. A technology computer-aided design model predicts that reducing surface-recombination velocity improves the efficiency limit to 48.6%. Free-carrier absorption and shadowing effects have been analyzed for their impact on TPV performance.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Physical
Jihun Lim, Bosun Roy-Layinde, Bin Liu, Andrej Lenert, Stephen R. Forrest
Summary: An air-bridge thermophotovoltaic (TPV) cell is demonstrated to achieve nearly complete utilization of out-of-band (OOB) photons. By using a flat In0.53Ga0.47As TPV membrane, the cell achieves an OOB reflectance (R (OOB)) of 98.9 +/- 0.1% under 1279 K blackbody illumination. The flat TPV cell exhibits improved spectral efficiency and power conversion efficiency compared to the buckled cell.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Bin Liu, Jason Lynch, Haonan Zhao, Ben R. Conran, Clifford McAleese, Deep Jariwala, Stephen R. Forrest
Summary: Atomically thin transition metal dichalcogenides (TMDs), a subclass of 2D layered materials, show promise as a platform for photonic and optoelectronic devices. This study demonstrates centimeter-scale monolayers of WS2 grown using metal-organic chemical vapor deposition, with polariton propagation lengths of up to 60 μm. The polaritons are formed through the coupling of excitons with Bloch surface waves (BSWs) supported by all-dielectric photonic structures. The results provide a practical approach for engineering long-range energy transport in TMD layers mediated by exciton-polaritons, enabling room temperature TMD-based polaritonic devices.
Correction
Multidisciplinary Sciences
Qiuyang Li, Adam Alfrey, Jiaqi Hu, Nathanial Lydick, Eunice Paik, Bin Liu, Haiping Sun, Yang Lu, Ruoyu Wang, Stephen Forrest, Hui Deng
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Boning Qu, Haonan Zhao, Stephen R. Forrest
Summary: A comprehensive numerical model is developed to quantitatively analyze the charge and exciton distributions in phosphorescent white organic light-emitting diodes (WOLEDs). The model is validated by direct measurement of the exciton distribution in monochromatic phosphorescent OLEDs and accurately predicts the intensity and current-dependent spectral shifts in complex, multilayer WOLEDs.
Article
Chemistry, Multidisciplinary
Xinjing Huang, Yongxi Li, Stephen R. Forrest
Summary: Blending dipolar NFA molecules in ternary organic photovoltaics (OPVs) reduces the operational stability due to the reorganization and reorientation of these molecules, which increases the dielectric constant of the bulk heterojunction (BHJ) and decreases the electric field, leading to a larger reduction in charge collection efficiency over time.
CELL REPORTS PHYSICAL SCIENCE
(2023)