Extremely high chromatic-stability white organic light-emitting device with symmetrical cascade emissive layer

Miao, Yanqin; Gao, Zhixiang; Wang, Hua; Jia, Husheng; Liu, Xuguang; Xu, Bingshe; Wei, Bin

doi:10.1016/j.orgel.2015.05.006

Cited by 21 publications

(23 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, for demonstrating high-quality WOLEDs, adequate complementary emitters are essential [3]. Here, phosphorescent tris(2-phenylpyridine)iridium(III)) (Ir(ppy) 3 ), Ir(ffpmq) 2 (acac), and bis(1-phenylisoquinoline)(acetylacetonate)iridium(III) (Ir(piq) 2 (acac)) were employed for green, yellow, and red emissions, respectively.…”

Section: Complementary Phosphors For Developing White Devicesmentioning

confidence: 99%

“…Here, phosphorescent tris(2-phenylpyridine)iridium(III)) (Ir(ppy) 3 ), Ir(ffpmq) 2 (acac), and bis(1-phenylisoquinoline)(acetylacetonate)iridium(III) (Ir(piq) 2 (acac)) were employed for green, yellow, and red emissions, respectively. The EL spectra of the three emitters were investigated from a common device with the structure of ITO/ N,N′-bis(naphthalen-1-yl) -N,N′-bis(phenyl)-benzidine (NPB) (40 nm)/ 4,4′-N,N′-dicarbazolylbiphenyl (CBP): 6 wt% emitter (30 nm)/ TPBi(35 nm)/ LiF(1 nm)/ Al(200 nm), in which the emitters were Ir(ppy) 3 , Ir(ffpmq) 2 (acac), and Ir(piq) 2 (acac), respectively. Along with the EL spectrum for device B3 at 6 V, the normalized EL spectra of the four emitters are displayed in Figure 2.…”

Section: Complementary Phosphors For Developing White Devicesmentioning

confidence: 99%

“…White organic light-emitting diodes (WOLEDs) have been widely studied in the past decades for their potential utilization in flat-panel displays and solid-state lighting, mainly due to their advantages, such as their high efficiency, transparency, flexibility, and exceptional light-weight, ultra-thin characteristics, to name a few [1][2][3][4]. In order to achieve high device efficiency, phosphorescent materials have been widely used to fabricate such devices because they allow manufacturers to harvest 25% singlet excitons and 75% triplet excitons, thus achieving internal quantum efficiency of 100%, compared with the 25% theoretical value for fluorescent materials [3][4][5][6][7][8].…”

Section: Introductionmentioning

confidence: 99%

“…In order to achieve high device efficiency, phosphorescent materials have been widely used to fabricate such devices because they allow manufacturers to harvest 25% singlet excitons and 75% triplet excitons, thus achieving internal quantum efficiency of 100%, compared with the 25% theoretical value for fluorescent materials [3][4][5][6][7][8]. However, the all-phosphorescent WOLEDs are limited by i) the absence of efficient blue phosphors with long operational lifetimes that are suitable for commercial applications [9,10], and ii) the difficulty of conducting carrier injection from an adjacent carrier transporting layer to the large-bandgap host material with higher triplet state energy [11].…”

Section: Introductionmentioning

confidence: 99%

“…Furthermore, several interlayers were still required during device fabrication. In fact, the excellent device stability and high CRI for WOLEDs are also key factors that are as important as other parameters, such as high efficiency, high brightness, and low cost [3,8,12,18,25,26]. Although some reported hybrid WOLEDs have realized high efficiency, problems still exist, including poor color stability and low CRI [10,15].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer

et al. 2017

Self Cite

View full text Add to dashboard Cite

By incorporating ultrathin (<0.1 nm) green, yellow, and red phosphorescence layers with different sequence arrangements in a blue fluorescence layer, four unique and simplified fluorescence/phosphorescence (F/P) hybrid, white organic light-emitting diodes (WOLEDs) were obtained. All four devices realize good warm white light emission, with high color rending index (CRI) of >80, low correlated color temperature of <3600 K, and high color stability at a wide voltage range of 5 V-9 V. These hybrid WOLEDs also reveal high forward-viewing external quantum efficiencies (EQE) of 17.82%-19.34%, which are close to the theoretical value of 20%, indicating an almost complete exciton harvesting. In addition, the electroluminescence spectra of the hybrid WOLEDs can be easily improved by only changing the incorporating sequence of the ultrathin phosphorescence layers without device efficiency loss. For example, the hybrid WOLED with an incorporation sequence of ultrathin red/yellow/ green phosphorescence layers exhibits an ultra-high CRI of 96 and a high EQE of 19.34%. To the best of our knowledge, this is the first WOLED with good tradeoff among device efficiency, CRI, and color stability. The introduction of ultrathin (<0.1 nm) phosphorescence layers can also greatly reduce the consumption of phosphorescent emitters as well as simplify device structures and fabrication process, thus leading to low cost. Such a finding is very meaningful for the potential commercialization of hybrid WOLEDs.

show abstract

Section: Complementary Phosphors For Developing White Devicesmentioning

confidence: 99%

Section: Complementary Phosphors For Developing White Devicesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

P‐164: Enabling High Performance Organic Light Emitting Diode with Novel Bi‐carbazole Host

Shahnawaz

Nagar

Swayamprabha

et al. 2020

Symp Digest of Tech Papers

View full text Add to dashboard Cite

The high performance of organic light‐emitting diodes (OLEDs) has been achieved with the utilization of the appropriate device architecture engineering and the development of novel materials. The synthesis of the efficient emitter and host materials is the important factor for realizing the higher device efficiency and the ideal performance. Herein, we have introduced a novel bi‐carbazole based host material, which exhibits high energy levels, high mobility, and triplet energy, enhancing the performance of the device. The comparative analysis of the device performance was carried with a different doping concentration of conventional yellow emitter PO‐01 into bi‐carbazole host emitter. As a result, the studied device reveals better performance at 15 wt% doping centration of PO‐01 yellow emitter. The device exhibits good performance as forward‐viewing power efficiency (PE), current efficiency (CE) and external quantum efficiency (EQE) of 19.2 lmW−1, 29.4 cdA−1 and 10.6 %, respectively at 100 cdm−2 brightness with a maximum luminance of 12250 cdm−2. It is also observed that the device shows PE, CE, and EQE of 11.3 lmW−1, 22.7 cdA−1, and 7.5 %, respectively at 1000 cdm−2. The optimal performance could be attributed due to effective host‐to‐guest energy transfer and balanced carrier injection. The results indicate that the development of bi‐carbazole materials may be utilized to maximize the performance of next‐generation lighting applications.

show abstract

High‐Performance Organic Electroluminescence: Design from Organic Light‐Emitting Materials to Devices

Tao

Miao

Wang

et al. 2018

The Chemical Record

Self Cite

View full text Add to dashboard Cite

Organic electroluminescence is considered as the most competitive alternative for the future solid-state displays and lighting techniques owing to many advantages such as selfluminescence, high efficiency, high contrast, high color rendering index, ultra-thin thickness, transparency, flat and flexibility, etc. The development of high-performance organic electroluminescence has become the continuing focus of research. In this personal account, a brief overview of representative achievements in our study on the design of highly efficient novel organic light-emitting materials (including fluorescent materials, phosphorescent iridium(III) complexes and conjugated polymers bearing phosphorescent iridium(III) complex) and highperformance device structures together with working principles are given. At last, we will give some perspectives on this fascinating field, and also try to provide some potential directions of research on the basis of the current stage of organic electroluminescence. Wiley Online Library 1537 Scheme 5. The chemical structures of cationic iridium(III) complexes based on various N N ligands (18-23).Figure 7. UV-vis absorption (a) and PL (b) of 18-23 in CH 2 Cl 2 . [30] Figure 35. (a) The device structure and proposed working mechanism for WOLED with sandwiched blue EML; (b) The normalized EL spectra of WOLED at the voltage of 5-7 V, and corresponding luminance, CIE, CCT, and CRI are also given. [65a]

show abstract

Extremely high chromatic-stability white organic light-emitting device with symmetrical cascade emissive layer

Cited by 21 publications

References 36 publications

High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer

High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer

P‐164: Enabling High Performance Organic Light Emitting Diode with Novel Bi‐carbazole Host

High‐Performance Organic Electroluminescence: Design from Organic Light‐Emitting Materials to Devices

Contact Info

Product

Resources

About