Electronic Structural Insight into High‐Performance Quantum Dot Light‐Emitting Diodes. (22nd September 2022)

• Record Type: Journal Article
• Authors: Cheng, Yang; Gui, Zhixiang; Qiao, Ruixi; Fang, Shucheng; Ba, Guohang; Liang, Tianyu; Wan, Haoyue; Zhang, Zhihong; Liu, Can; Ma, Chaojie; Hong, Hao; Fan, Fengjia; Liu, Kaihui; Shen, Huaibin
• Is Part Of: Advanced functional materials. Volume 32:Number 48(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-22
• Subjects: charge transport properties -- in situ electroluminescence -- in situ photoluminescence -- phase engineering -- QD‐LED; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202207974
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Quantum dot light‐emitting diodes (QD‐LEDs) are highly promising light sources with excellent figures of merit. Although great successes have been achieved in elevating some key parameters to an ideal level, QD‐LEDs with superior performance in all aspects have rarely been realized. Herein, by exploring crystalline structure‐dependent electronic properties, it is shown that QD‐LEDs can simultaneously exhibit high external quantum efficiency, roll‐off‐free under high brightness, and dramatically improved operational stability. This improved performance stems from the crystal phase engineering of QD. Reduced structure symmetry in the wurtzite phase introduces an unneglectable internal crystal field compared with the zinc‐blende one, which raises both the conduction and valence band energy levels, thus, facilitating a more balanced charge injection. The crystal phase‐optimized superior‐comprehensive performance in the QD‐LED offers a novel degree of freedom for device engineering and promotes commercial applications for the upcoming display and illumination technologies. Abstract : Crystalline structure‐dependent electronic properties have been understood thoroughly in quantum dot light‐emitting diodes in this work. QD‐LEDs can simultaneously exhibit high external quantum efficiency, roll‐off‐free under high brightness, and dramatically improved operation stability by crystal phase engineering.