Dual-Phase Regulation for High-Efficiency Perovskite Light-Emitting Diodes

Perovskite light-emitting diodes (Pero-LEDs) have attracted significant attention due to their high color purity and solution processing, presenting potential applications for next-generation solid-state lighting and displays. Continued materials development has shown that passivating non-radiative defects can improve device performance. In theory, CsPbBr3&Cs4PbBr6 should be a model emitter for Pero-LEDs, as its lattice matching provides ideal passivation and efficient exciton confinement. However, the low charge transport of Cs4PbBr6 has so far hindered device performance. Herein, a dual-phase regulation method to grow a CsPbBr3&Cs4PbBr6 perovskite layer that enables efficient electrical injection is developed. This leads to the realization that Pero-LEDs with a maximum EQE of 22.3% with a luminance of 10,050 cd m(-2), and the devices show a T-50 of 59 h at 130 cd m(-2).