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

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 CsPbBr3 -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 (T50 ) 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.