Unravelling Alkali-Metal-Assisted Domain Distribution of Quasi-2D Perovskites for Cascade Energy Transfer toward Efficient Blue Light-Emitting Diodes

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

40 Scopus Citations
View graph of relations

Author(s)

  • Wanqing Cai
  • Muhammad Umair Ali
  • Ping Liu
  • Miao He
  • Cong Zhao
  • Ziming Chen
  • Yue Zang
  • Man-Chung Tang
  • Hong Meng
  • Hongyan Fu
  • Guodan Wei

Detail(s)

Original languageEnglish
Article number2200393
Journal / PublicationAdvanced Science
Volume9
Issue number20
Online published13 May 2022
Publication statusPublished - 15 Jul 2022

Link(s)

Abstract

Solution processable quasi-2D (Q-2D) perovskite materials are emerging as a promising candidate for blue light source in full-color display applications due to their good color saturation property, high brightness, and spectral tunability. Herein, an efficient energy cascade channel is developed by introducing sodium bromide (NaBr) in phenyl-butylammonium (PBA)-containing mixed-halide Q-2D perovskites for a blue perovskite light-emitting diode (PeLED). The incorporation of alkali metal contributes to the nucleation and growth of Q-2D perovskites into graded distribution of domains with different layer number <n>. The study of excitation dynamics by transient absorption (TA) spectroscopy confirms that NaBr induces more Q-2D perovskite phases with small n number, providing a graded energy cascade pathway to facilitate more efficient energy transfer processes. In addition, the nonradiative recombination within the Q-2D perovskites is significantly suppressed upon Na+ incorporation, as validated by the trap density estimation. Consequently, the optimized blue PeLEDs manifest a peak external quantum efficiency (EQE) of 7.0% emitting at 486 nm with a maximum luminance of 1699 cd m−2. It is anticipated that these findings will improve the understanding of alkali-metal-assisted optimization of Q-2D perovskites and pave the way toward high-performance blue PeLEDs.

Research Area(s)

  • alkali metal halide, domain distribution, perovskite light-emitting diode, quasi-2D perovskite

Citation Format(s)

Unravelling Alkali-Metal-Assisted Domain Distribution of Quasi-2D Perovskites for Cascade Energy Transfer toward Efficient Blue Light-Emitting Diodes. / Cai, Wanqing; Ali, Muhammad Umair; Liu, Ping et al.
In: Advanced Science, Vol. 9, No. 20, 2200393, 15.07.2022.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

Download Statistics

No data available