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Proton-Prompted Ligand Exchange to Achieve High-Efficiency CsPbI₃ Quantum Dot Light-Emitting Diodes.

ABSTRACT: CsPbI₃ perovskite quantum dots (QDs) are ideal materials for the next generation of red light-emitting diodes. However, the low phase stability of CsPbI₃ QDs and long-chain insulating capping ligands hinder the improvement of device performance. Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control. Here, we proposed a new ligand exchange strategy using a proton-prompted in-situ exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI₃ QDs. This exchange strategy maintained the size and morphology of CsPbI₃ QDs and improved the optical properties and the conductivity of CsPbI₃ QDs films. As a result, high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45% and an operational half-life of 10.79 h.

SUBMITTER: Li Y

PROVIDER: S-EPMC10834927 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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Proton-Prompted Ligand Exchange to Achieve High-Efficiency CsPbI3 Quantum Dot Light-Emitting Diodes.

Li Yanming Y Deng Ming M Zhang Xuanyu X Qian Lei L Xiang Chaoyu C

Nano-micro letters 20240201 1

CsPbI3 perovskite quantum dots (QDs) are ideal materials for the next generation of red light-emitting diodes. However, the low phase stability of CsPbI3 QDs and long-chain insulating capping ligands hinder the improvement of device performance. Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control. Here, we proposed a new ligand exchange strategy using a proton-prompted in-situ exchange of short 5-aminopentanoic acid lig ...[more]

PMID: 38300363

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