Air-Stable Ultrabright Inverted Organic Light-Emitting Devices with Metal Ion-Chelated Polymer Injection Layer

Shihao Liu; Chunxiu Zang; Jiaming Zhang; Shuang Tian; Yan Wu; Dong Shen; Letian Zhang; Wenfa Xie; Chun-Sing Lee

doi:10.1007/s40820-021-00745-w

Air-Stable Ultrabright Inverted Organic Light-Emitting Devices with Metal Ion-Chelated Polymer Injection Layer

Nanomicro Lett. 2021 Dec 6;14(1):14. doi: 10.1007/s40820-021-00745-w.

Authors

Shihao Liu^#^{1

2}, Chunxiu Zang^#¹, Jiaming Zhang¹, Shuang Tian², Yan Wu², Dong Shen², Letian Zhang¹, Wenfa Xie³, Chun-Sing Lee⁴

Affiliations

¹ State Key Laboratory of Integrated Optoelectronics, College of Electronics Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, People's Republic of China.
² Department of Chemistry, Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China.
³ State Key Laboratory of Integrated Optoelectronics, College of Electronics Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, People's Republic of China. xiewf@jlu.edu.cn.
⁴ Department of Chemistry, Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China. apcslee@cityu.edu.hk.

^# Contributed equally.

Abstract

Here, this work presents an air-stable ultrabright inverted organic light-emitting device (OLED) by using zinc ion-chelated polyethylenimine (PEI) as electron injection layer. The zinc chelation is demonstrated to increase the conductivity of the PEI by three orders of magnitude and passivate the polar amine groups. With these physicochemical properties, the inverted OLED shows a record-high external quantum efficiency of 10.0% at a high brightness of 45,610 cd m^-2 and can deliver a maximum brightness of 121,865 cd m^-2. Besides, the inverted OLED is also demonstrated to possess an excellent air stability (humidity, 35%) with a half-brightness operating time of 541 h @ 1000 cd m^-2 without any protection nor encapsulation.

Keywords: Air stability; Electron injection; Inverted organic light-emitting device; Metal ion chelation; Ultrabright.