Balanced white organic light-emitting diode with non-doped ultra-thin emissive layers based on exciton management

Tan, Te; Ouyang, Shihong; Xie, Yingtao; Wang, Dongping; Zhu, Dong Mei; Xu, Xin; Fong, Hon Hang

doi:10.1016/j.orgel.2015.06.044

Cited by 22 publications

(16 citation statements)

References 15 publications

(18 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the thickness of the green dyes increased, more excitons will be consumed by the Ir(ppy) 2 (acac) rather than the FIrpic, resulting in a decrease of blue emission. Second, the bluish-green emission may be due to Forster transfer since their distances were spatially located within the Forster radii 24 . Figure 4b shows the variation of EL spectra, brightness and CIE with increasing driving voltage for the device consisting of 0.02 nm thick of Ir(ppy) 2 (acac).…”

Section: Resultsmentioning

confidence: 99%

“…Chen et al 23 replaced conventional host-dopant systems with non-doped ultrathin bluish-green and red dyes to achieve high-efficiency white OLEDs. Tan et al 24 . adopted the UEML approach to fabricate white OLEDs with an efficiency of 23.4 cd/A and 17.0 lm/W.…”

mentioning

confidence: 99%

“…Recently, OLEDs with dopant-free and ultrathin emissive layers (UEMLs) have aroused much attention 22 23 24 25 26 27 28 29 30 31 32 . Chen et al 23 replaced conventional host-dopant systems with non-doped ultrathin bluish-green and red dyes to achieve high-efficiency white OLEDs.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Highly Efficient White Organic Light-Emitting Diodes with Ultrathin Emissive Layers and a Spacer-Free Structure

Sun

et al. 2016

Sci Rep

View full text Add to dashboard Cite

Ultrathin emissive layers (UEMLs) of phosphorescent materials with a layer thickness of less than 0.3 nm were introduced for high-efficiency organic light-emitting diodes (OLEDs). All the UEMLs for white OLEDs can be prepared without the use of interlayers or spacers. Compared with devices fabricated with interlayers inserted in-between the UEMLs, our spacer-free structure not only significantly improves device efficiency, but also simplifies the fabrication process, thus it has a great potential in lowering the cost of OLED panels. In addition, its spacer-free structure decreases the number of interfaces which often introduce unnecessary energy barriers in these devices. In the present work, UEMLs of red, green and blue-emitting phosphorescent materials and yellow and blue phosphorescent emitters are utilized for the demonstration of spacer-free white OLEDs. Upon optimization of the device structure, we demonstrated spacer-free and simple-structured white-emitting OLEDs with a good device performance. The current and power efficiencies of our white-emitting devices are as high as 56.0 cd/A and 55.5 lm/W, respectively. These efficiencies are the highest ever reported for OLEDs fabricated with the UEML approach.

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Highly Efficient White Organic Light-Emitting Diodes with Ultrathin Emissive Layers and a Spacer-Free Structure

Sun

et al. 2016

Sci Rep

View full text Add to dashboard Cite

show abstract

“…To simplify the fabrication process of OLEDs without reducing the device efficiency, the doping‐free ultrathin emitting layer (UEML) structure, which generally inserts a thin emitting layer (thickness <1 nm) between the hole transport layer (HTL) and the electron transport layer (ETL), has drawn increasing attention . Zhao et al reported ultrathin non‐doped blue, green, red, and white PHOLEDs with maximum external quantum efficiency (EQE) of 17.1%, 20.9%, 19.2%, and 18.5%, respectively .…”

Section: Introductionmentioning

confidence: 99%

High Efficiency Non‐Doped White Organic Light Emitting Diodes Based on a Bilayer Interface‐Exciplex Structure

Wang

Dong

et al. 2019

Physica Status Solidi (a)

View full text Add to dashboard Cite

High efficiency non-doped blue and white organic light emitting diodes (OLEDs) are realized by using a bilayer interface-exciplex (i-Exc) structure. Since the neutral exciplex are formed at the interface, the interface charge accumulation is reduced, thereby suppressing exciton quenching in the device. With the i-Exc structure, a maximum external quantum efficiency (EQE) of 23.1% is achieved in the non-doped blue phosphorescent OLED. Moreover, the white emission can be obtained by inserting an ultrathin orange-red phosphorescent emitter into the blue devices. The charge trapping in the orange-red emitter can be suppressed by adjusting the position of the ultrathin orange-red emitting layer in the device, contributing to superior spectral stability. The WOLED achieves an EQE of 20.0% and exhibits a stable warm white emission. The Commission Internationale de l'Eclairage (CIE) coordinates of WOLED are (0.41, 0.40) at 5 V and slightly change to (0.40, 0.41) at 9 V.

show abstract

“…It has been shown that by introducing a non-doped pure organic EML in hybrid WOLEDs, this device can gain higher efficiency than that of the conventional host-guest doped device. Tan et al demonstrated highly efficient WOLED structure with non-doped ultra-thin EMLs to investigate the spatial distribution of excitons [28]. Such non-doped devices allow us easily to optimize and construct EML independently [22,29,30].…”

Section: Introductionmentioning

confidence: 99%

Management of Exciton for Highly-Efficient Hybrid White Organic Light-Emitting Diodes with a Non-Doped Blue Emissive Layer

et al. 2019

View full text Add to dashboard Cite

Hybrid white organic light-emitting diodes (WOLEDs) have drawn great attention both for display and solid-state lighting purposes because of the combined advantages of desirable stability of fluorescent dyes and high efficiency of phosphorescent materials. However, in most WOLEDs, obtaining high efficiency often requires complex device structures. Herein, we achieved high-efficiency hybrid WOLEDs using a simple but efficacious structure, which included a non-doped blue emissive layer (EML) to separate the exciton recombination zone from the light emission region. After optimization of the device structure, the WOLEDs showed a maximum power efficiency (PE), current efficiency (CE), and external quantum efficiency (EQE) of 82.3 lm/W, 70.0 cd/A, and 22.2%, respectively. Our results presented here provided a new option for promoting simple-structure hybrid WOLEDs with superior performance.

show abstract

Balanced white organic light-emitting diode with non-doped ultra-thin emissive layers based on exciton management

Cited by 22 publications

References 15 publications

Highly Efficient White Organic Light-Emitting Diodes with Ultrathin Emissive Layers and a Spacer-Free Structure

Highly Efficient White Organic Light-Emitting Diodes with Ultrathin Emissive Layers and a Spacer-Free Structure

High Efficiency Non‐Doped White Organic Light Emitting Diodes Based on a Bilayer Interface‐Exciplex Structure

Management of Exciton for Highly-Efficient Hybrid White Organic Light-Emitting Diodes with a Non-Doped Blue Emissive Layer

Contact Info

Product

Resources

About