Light-Emitting Diodes In article number 2405272, Tae-Woo Lee and co-workers report on a high-performance perovskite light-emitting diode device achieved through the introduction of 1,8-octanedithiol (ODT). This additive effectively passivates defects within the MAPbBr3 perovskite emitter and at the interface with the hole injection layer. The inset illustrates how ODT prevents exciton quenching by defect passivation, significantly enhancing luminescent properties and device efficiency.