Strongly-Confined CsPbI3 Quantum Dots by Surface Cleaning-Induced Ligand Exchange for Spectrally Stable Pure-Red Light-Emitting Diodes with Efficiency Exceeding 26%

Ke Ren, Jingcong Hu, Chenghao Bi, Shibo Wei, Xingyu Wang, Nora H. de Leeuw, Yue Lu, Manling Sui, Wenxin Wang

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

The advancement of pure-red perovskite light-emitting diodes (PeLEDs) is still a challenge because of surface “wastes” (like surface vacancies and excessive insulating ligands) on quantum dots (QDs). Herein, we develop a method to synthesize single-halide pure-red CsPbI3 QDs, combining a strong quantum confinement effect and meticulous surface-cleaning-induced ligand exchange. We achieve pure-red emitting QDs by controlling the size and uniformity under iodide-rich conditions. Subsequently, vacancy defects and insulating ligands are cleared through introducing acid. Then this surface-cleaning process induces ligand exchange to further inhibit the nonradiative recombination and improve the electrical property of QDs. These QDs show a pure-red photoluminescence (PL) at 635 nm with the PL quantum yield (PLQY) of 99%. Finally, PeLEDs, which utilize these QDs, demonstrate a pure-red electroluminescence (EL) peak at 638 nm with a maximum external quantum efficiency (EQE) of 26.0%

Original languageEnglish
Pages (from-to)4115–4123
Number of pages9
JournalACS Materials Letters
Volume6
Issue number9
Early online dateAug 2024
DOIs
Publication statusPublished - 7 Aug 2024

Bibliographical note

Publisher Copyright:
© 2024 American Chemical Society.

Funding

We gratefully acknowledge all of the funds which support this work. This work is financially supported by the National Natural Science Foundation of China (Nos. 52302171, 12074016 and 12274009), Shandong Provincial Natural Science Foundation, China (ZR2023QF005), Heilongjiang Provincial Natural Science Foundation of China (LH2023F026, LH2020A007 and LH2020F027), New Era Longjiang Excellent Doctoral Dissertation Project (LJYXL2022-003), the Research and Development Project from the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering (2022SX-TD001), Teaching Reform Research Project of Harbin Engineering University (79005023/013) and the Fundamental Research Funds for the Central Universities (3072024XX2606, 3072022TS2613, 79000012/012).

FundersFunder number
Beijing Excellent Doctoral Thesis ProjectLJYXL2022-003
National Aerospace Science Foundation of China12074016, 12274009, 52302171
Harbin Engineering University79005023/013
Shandong Provincial Education Science PlanZR2023QF005
Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering2022SX-TD001
Heilongjiang Postdoctoral Science FoundationLH2020A007, LH2023F026, LH2020F027
Support Program for Longyuan Youth and Fundamental Research Funds for the Universities of Gansu Province3072024XX2606, 3072022TS2613, 79000012/012

    Keywords

    • Nanocrystals
    • Perovskite
    • Stability

    Fingerprint

    Dive into the research topics of 'Strongly-Confined CsPbI3 Quantum Dots by Surface Cleaning-Induced Ligand Exchange for Spectrally Stable Pure-Red Light-Emitting Diodes with Efficiency Exceeding 26%'. Together they form a unique fingerprint.

    Cite this