Elevating Standard-Red Perovskite LED Performance: Unleashing Optimal Potential with Complex HTL and Insert Modification Layer

In this study, we introduce a novel strategy to improve the productivity of perovskite light-emitting diodes (PeLEDs) by incorporating a KBr interface layer alongside PEDOT:PSS as the hole transport layer (HTL). This innovative approach enables the creation of a standard-red perovskite film emitting light precisely at 630 nm. Our investigation demonstrates that optimizing the concentration of the KBr modified layer (10 mg ml −1 ), in conjunction with an ethylene glycol (EG)-doped PEDOT:PSS electrode, promotes the growth of CsPbBr 1.3 I 1.7 perovskite phases on the HTL while effectively reducing exciton quenching in PEDOT:PSS-based PeLEDs. Furthermore, these modifications lower the work function of the PEDOT:PSS surface, thus regulating hole injection and improving charge balance within the device. Consequently, our device achieves impressive performance metrics, including a high quantum yield of 68.2%, maximum luminance ( L max ) of 747 cd m −2 , and an External Quantum Efficiency (EQE) of 0.24%, representing significant advancements in red perovskite-based lighting technology.