High Efficiency and Low Roll-Off Pure-Red Perovskite LED Enabled by Simultaneously Inhibiting Auger and Trap Recombination of Quantum Dots.
Nano Lett
; 24(21): 6410-6416, 2024 May 29.
Article
en En
| MEDLINE
| ID: mdl-38767286
ABSTRACT
CsPbI3 perovskite quantum dots (QDs) could achieve pure-red emission by reducing their size, but the increased exciton binding energy (EB) and surface defects for the small-sized QDs (SQDs) cause severe Auger and trap recombinations, thus worsening their electroluminescence (EL) performance. Herein, we utilize the dangling bonds of the SQDs as a driving force to accelerate KI dissolution to solve its low solubility in nonpolar solvents, thereby allowing K+ and I- to bond to the surface of SQDs. The EB of the SQDs was decreased from 305 to 51 meV because of the attraction of K+ to electrons, meanwhile surface vacancies were passivated by K+ and I-. The Auger and trap recombinations were simultaneously suppressed by this difunctional ligand. The SQD-based light-emitting diode showed a stable pure-red EL peak of 639 nm, an external quantum efficiency of 25.1% with low roll-off, and a brightness of 5934 cd m-2.
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1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
Nano Lett
Año:
2024
Tipo del documento:
Article
País de afiliación:
China