Manipulating Local Lattice Distortion for Spectrally Stable and Efficient Mixed-halide Blue Perovskite LEDs.
Angew Chem Int Ed Engl
; 62(21): e202302184, 2023 May 15.
Article
em En
| MEDLINE
| ID: mdl-36866612
ABSTRACT
Mixed-halide perovskites are considered the most straightforward candidate to realize blue perovskite light-emitting diodes (PeLEDs). However, they suffer severe halide migration, leading to spectral instability, which is particularly exaggerated in high chloride alloying perovskites. Here, we demonstrate energy barrier of halide migration can be tuned by manipulating the degree of local lattice distortion (LLD). Enlarging the LLD degree to a suitable level can increase the halide migration energy barrier. We herein report an "A-site" cation engineering to tune the LLD degree to an optimal level. DFT simulation and experimental data confirm that LLD manipulation suppresses the halide migration in perovskites. Conclusively, mixed-halide blue PeLEDs with a champion EQE of 14.2 % at 475â
nm have been achieved. Moreover, the devices exhibit excellent operational spectral stability (T50 of 72â
min), representing one of the most efficient and stable pure-blue PeLEDs reported yet.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2023
Tipo de documento:
Article