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Vol. 9 No. 4 (2017)

Regulating Charge and Exciton Distribution in High-Performance Hybrid White Organic Light-Emitting Diodes with n-Type Interlayer Switch

https://doi.org/10.1007/s40820-017-0138-4
Dongxiang Luo
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yanfeng Yang
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Ye Xiao
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yu Zhao
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yibin Yang
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Baiquan Liu
Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People’s Republic of China

Corresponding Author: Baiquan Liu

bqliu1012@gmail.com

Nano-Micro Letters, Vol. 9 No. 4 (2017), Article Number: 37

Abstract

The interlayer (IL) plays a vital role in hybrid white organic light-emitting diodes (WOLEDs); however, only a negligible amount of attention has been given to n-type ILs. Herein, the n-type IL, for the first time, has been demonstrated to achieve a high efficiency, high color rendering index (CRI), and low voltage trade-off. The device exhibits a maximum total efficiency of 41.5 lm W−1, the highest among hybrid WOLEDs with n-type ILs. In addition, high CRIs (80–88) at practical luminances (≥1000 cd m−2) have been obtained, satisfying the demand for indoor lighting. Remarkably, a CRI of 88 is the highest among hybrid WOLEDs. Moreover, the device exhibits low voltages, with a turn-on voltage of only 2.5 V (>1 cd m−2), which is the lowest among hybrid WOLEDs. The intrinsic working mechanism of the device has also been explored; in particular, the role of n-type ILs in regulating the distribution of charges and excitons has been unveiled. The findings demonstrate that the introduction of n-type ILs is effective in developing high-performance hybrid WOLEDs.


Highlights:


1 The n-type interlayer was demonstrated to achieve a high efficiency, high color rendering index (CRI), and low voltage trade-off. The device exhibits a maximum total efficiency of 41.5 lm W−1 and a low turn-on voltage of 2.5 V (>1 cd m−2).
2 High CRIs (80–88) at practical luminances (≥1000 cd m−2) were obtained, with a CRI of 88 being the highest among hybrid WOLEDs.

Keywords

White light Hybrid Interlayer Color rendering index Organic light-emitting diodes
Luo, Dongxiang, Yanfeng Yang, Ye Xiao, Yu Zhao, Yibin Yang, and Baiquan Liu. 2017. “Regulating Charge and Exciton Distribution in High-Performance Hybrid White Organic Light-Emitting Diodes With N-Type Interlayer Switch”. Nano-Micro Letters 9 (4):37. https://doi.org/10.1007/s40820-017-0138-4.
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