Efficient Solution-Processed Green InP-Based Quantum Dot Light-Emitting Diodes With a Stepwise Hole Injection Layer

作者：Zhao, Yongshuang; Wu, Jialin; Chen, Lixiang^*; Qiu, Xuejun; Tan, Xingwen; Lei, Yanlian^*

来源：IEEE Electron Device Letters, 2022, 43(3): 410-413.

DOI：10.1109/LED.2022.3147350

• Green products
• Three-dimensional displays
• Performance evaluation
• Light emitting diodes
• II-VI semiconductor materials
• Energy states
• Charge carrier processes
• InP quantum dots
• light-emitting diodes
• hole injection layer
• electroluminescence

The intrinsic toxicity-free indium phosphide (InP) quantum dots (QDs) are regarded as the most promising alternative to the heavy metal-containing QDs for quantum dot light-emitting diodes (QLEDs) in next-generation display and lighting applications. Here, a stepwise hole injection layer consisting of PEDOT:PSS and solution-processed molybdenum oxide is employed to improve the hole injection for solution-processed green QLEDs based on InP/ZnSe/ZnS colloidal QDs. The hole transport layer (HTL) of poly(vinylcarbazole) with high-lying LUMO level is further used to block electrons. As a result, the electron-hole recombination zone is restricted in the middle of the InP/ZnSe/ZnS QDs emissive layer, reducing the possibility of exciton quenching at HTL and/or the HTL/QDs interface. This enables high-efficiency green InP-based QLEDs with the peak external quantum efficiency, current efficiency, and luminance of 5.84%, 20.8 cd/A, 5145 cd/m(2), respectively.

• 单位
  西南大学; 广东药学院