Stabilizing electroluminescence color of blue perovskite LEDs via amine group doping
| Autor: | Jizhong Song, Fengjuan Zhang, Xi Chen, Bo Cai, Changting Wei, Haibo Zeng, Tao Fang |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Multidisciplinary
Materials science Dopant business.industry Doping Electroluminescence 010502 geochemistry & geophysics 01 natural sciences law.invention Formamidinium Quantum dot law Optoelectronics Quantum efficiency business 0105 earth and related environmental sciences Light-emitting diode Perovskite (structure) |
| Zdroj: | Science Bulletin. 66:2189-2198 |
| ISSN: | 2095-9273 |
| Popis: | Voltage loading-induced change in the electroluminescence (EL) wavelength of mixed halide perovskite light-emitting diodes (PeLEDs), so-called color-shift, has become an inevitable phenomenon, which is seriously unfavorable to their applications in lighting and display. Here, we achieve color-stable blue PeLEDs via a hydrogen-bonded amine-group doping strategy. Selecting guanidine (GA) or formamidinium (FA) as amine-group (−NH2) doping source for CsPbBrxCl3−x quantum dots (QDs), experimental and theoretical results reveal that the strong N−H⋯X (X = Br/Cl) bonding can be produced between −NH2 dopants and Pb−X lattices, thereby increasing the migration barrier of halide anions. Resultantly, color-stable sky-blue devices were realized with emission peaks fixed at 490.5 (GA) and 492.5 (FA) nm without any obvious shift as the voltage increases, in sharp contrast devices without N−H⋯X producing a 15 nm red-shift from 487 to 502 nm. Not only that, maximum external quantum efficiency is improved to 3.02% and 4.14% from the initial 1.3%. This finding offers a convenient boulevard to achieve color-stable PeLEDs with high efficiency. |
| Databáze: | OpenAIRE |
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