Wei, S., Hu, J., Bi, C. et al. (6 more authors) (2024) Strongly-Confined CsPbBr₃ Perovskite Quantum Dots with Ultralow Trap Density and Narrow Size Distribution for Efficient Pure-Blue Light-Emitting Diodes. Small, 20 (36). 2400885. ISSN 1613-6810
Abstract
The development of pure-blue perovskite light-emitting diodes (PeLEDs) faces challenges of spectral stability and low external quantum efficiency (EQE) due to phase separation in mixed halide compositions. Perovskite quantum dots (QDs) with strong confinement effects are promising alternatives to achieve high-quality pure-blue PeLEDs, yet their performance is often hindered by the poor size distribution and high trap density. A strategy combining thermodynamic control with a polishing-driven ligand exchange process to produce high-quality QDs is developed. The strongly-confined pure-blue (≈470 nm) CsPbBr₃ QDs exhibit narrow size distribution (12% dispersion) and are achieved in Br-rich ion environment based on growth thermodynamic control. Subsequent polishing-driven ligand exchange process removes imperfect surface sites and replaces initial long-chain organic ligands with short-chain benzene ligands. The resulting QDs exhibit high photoluminescence quantum yield (PLQY) to near-unity. The resulting PeLEDs exhibit a pure-blue electroluminescence (EL) emission at 472 nm with narrow full-width at half-maximum (FWHM) of 25 nm, achieving a maximum EQE of 10.7% and a bright maximum luminance of 7697 cd m⁻². The pure-blue PeLEDs show ultrahigh spectral stability under high voltage, a low roll-off of EQE, and an operational half-lifetime (T₅₀) of 127 min at an initial luminance of 103 cd m⁻² under continuous operation.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024 Wiley-VCH GmbH. This is the peer reviewed version of the following article: S. Wei, J. Hu, C. Bi, K. Ren, X. Wang, N. H. de de Leeuw, Y. Lu, M. Sui, W. Wang, Strongly-Confined CsPbBr3 Perovskite Quantum Dots with Ultralow Trap Density and Narrow Size Distribution for Efficient Pure-Blue Light-Emitting Diodes. Small 2024, 2400885, which has been published in final form at https://doi.org/10.1002/smll.202400885. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. |
Keywords: | perovskite light-emitting diodes; perovskite quantum dots; polishing-driven ligand exchange; pure-blue emission; size distribution |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 09 Apr 2024 09:32 |
Last Modified: | 18 Feb 2025 14:42 |
Status: | Published |
Publisher: | Wiley |
Identification Number: | 10.1002/smll.202400885 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:211304 |
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Filename: Manuscript-Blue PeLED-for publication 1221.pdf

Filename: Supporting Information-20221217.pdf
