Interfacial Charge Modulation: An Efficient Strategy for Stable Blue Quantum‐Dot Light‐Emitting Diodes

• Published in: Advanced optical materials 2023-01, Vol.11 (2), p.n/a
• Main Authors: Liang, Shanshan, Wang, Shujie, Wu, Ziho, Wen, Bo, Cai, Guofa, Jiang, Xiaohong, Huang, Guangguang, Li, Chenguang, Zhao, Yaolong, Du, Zuliang
• Format: Article
• Language: English
• Subjects: blue quantum‐dot light‐emitting diodes; Density functional theory; Electron transport; electron transport layer; interface modification; Light emitting diodes; Materials science; monolayer Ti 3C 2T x; Optics; Optoelectronic devices; Photoelectric emission; Quantum dots; Two dimensional materials; Work functions
• ISSN: 2195-1071; 2195-1071
• DOI: 10.1002/adom.202201802

Quantum‐dot light‐emitting diodes (QLEDs) are proposed as one of the most promising candidates for next‐generation displays, but their commercial application is seriously limited due to the poor performance of blue QLEDs (B‐QLEDs). Herein, this work uses Ti3C2Tx nanosheets to tune the work function (WF) of ZnMgO and to engineer the quantum dot (QD)/electron transport layer (ETL) interface. The B‐QLEDs with ZnMgO‐Ti3C2Tx hybrid ETL exhibit a maximum EQE of 15.81% and a remarkable T50 operation lifetime of 3284 h at 100 cd m−2. In addition to that, ultraviolet photoemission spectroscopy and density functional theory calculations both confirm that the addition of Ti3C2Tx to ZnMgO can effectively tune the ZnMgO's work function, further give rise to the reduction of QD/ETL energy barrier, which finally results in the alleviation of charge accumulation at the QD/ETL interface. The findings of interface engineering by Ti3C2Tx not only provide a promising strategy for the application of 2D materials in optoelectronic devices, but also pave the way to construct high‐performance light‐emitting diodes. A stable and efficient blue quantum‐dot light‐emitting diode is achieved by using ZnMgO‐Ti3C2Tx as electron transport layer (ETL). The addition of Ti3C2Tx to ZnMgO can effectively tune the ZnMgO's work functions, further give rise to the reduction of quantum dot (QD)/ETL energy barrier, which finally results in the alleviation of charge accumulation at the QD/ETL interface.