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.[Figure not available: see fulltext.].
Original language | English |
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Article number | 105 |
Journal | Nano-Micro Letters |
Volume | 16 |
Issue number | 1 |
DOIs | |
Publication status | Published - Dec 2024 |
Keywords
- CsPbI perovskite quantum dots
- Ligand exchange
- Light-emitting diodes
- Proton-prompted in-situ exchange
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering