Abstract
Inorganic perovskite quantum dots (QDs) have garnered significant attention due to their outstanding optical properties. However, perovskite quantum dot light-emitting diodes (Pe-QLEDs) still face challenges related to their fluorescence efficiency and electron injection. First, the electron transport layer (ETL) leads to severe non-radiative recombination due to fluorescence quenching in CsPbI3 QDs. Second, there is an electron injection imbalance resulting from low electron injection efficiency, leading to reduced non-radiative recombination and external quantum efficiency. To address these issues, this study introduces two interface layer materials with different electron affinities, 1,3,5-Tris(3-pyridyl-3-phenyl)benzene (TmPyPB) and 2,4,6-Tris(3′-(pyridine-3-yl)biphenyl-3-yl)-1,3,5-triazine (TmPPPyTz). These materials not only passivated defects on the surface of CsPbI3 QDs films but also effectively prevented the fluorescence quenching of CsPbI3 QDs by the PO-T2T (ETL). TmPPPyTz, with a relatively lower LUMO energy level, further improved energy level matching, significantly enhancing electron injection efficiency. Ultimately, using interface engineering with the TmPPPyTz interface layer, the devices achieved an outstanding 25.80% champion-level external quantum efficiency (EQE) for Pe-QLEDs with only a sub-bandgap voltage of 1.7 V and half-life (T50) is 17.99 h at 100 nits. This research provided an effective method to enhance the performance of CsPbI3 Pe-QLEDs, addressing long-standing issues inhibiting their efficiency.
Original language | English |
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Article number | 2302758 |
Journal | Advanced Optical Materials |
Volume | 12 |
Issue number | 13 |
DOIs | |
Publication status | Published - 6 May 2024 |
Keywords
- electron injection
- inorganic perovskite quantum dots
- interface engineering
- optoelectronic performance
- strong electron affinity
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics