High Curvature PEDOT:PSS Transport Layer Toward Enhanced Perovskite Light‐Emitting Diodes

Abstract The rapidly developed metal halide perovskite light‐emitting diodes (PeLEDs) are considered as a promising candidate for next‐generation display and illumination, but the unbalanced charge transport is still a hard‐treat case to restrict its efficiency and operational stability. Here, a high curvature PEDOT:PSS transport layer is demonstrated via the self‐assembly island‐like structures by the incorporation of alkali metal salts. Benefiting from the dielectric confinement effect of the high curvature surface, the modified CsPbBr 3 ‐based PeLEDs present a 2.1 times peak external quantum efficiency (EQE) from 6.75% to 14.23% and a 3.3 times half lifetime ( T 50 ) from 3.96 to 13.01 h. Besides, the PeLEDs show high luminance up to 44834 cd m −2 . Evidently, this work may provide a deep insight into the structure‐activity relationship between the micro‐structures at the PEDOT:PSS/perovskite interface and the performance of PeLEDs, and crack the codes for ameliorating the performance of PeLEDs via interfacial micro‐structured regulation.