Addressing the 1000-h/1000-nit stability challenge in perovskite LEDs

Abstract Perovskite light-emitting diodes (PeLEDs) offer exceptional colour purity and efficiency for next-generation display applications. Despite the recent advances in device stability, achieving long-term stable PeLEDs under display-relevant conditions remains a critical challenge. The actual device half-life (T 50 ) experimentally measured for visible PeLEDs were in most cases limited to below 1000 h for any given brightness, in contrast to the much longer extrapolated lifetimes reported. Here, we demonstrate stable green PeLEDs with a T 50 lifetime of 1350 h at an initial luminance of 1000 cd m −2 (nits), a maximum energy-conversion efficiency of 28.0%, and a peak external quantum efficiency of 24.5%. The exceptional performance is enabled by the insertion of a fluorinated self-assembled monolayer between the metal oxide and polymeric hole-transport layers. This molecular interlayer leads to Ohmic-like characteristics for charge injection, lowering the operating voltage at ~1000 nits to sub-bandgap levels (~2.1 V) where ion migration is suppressed. The accumulated photon output of our PeLEDs over the course of their T 50 lifespan is found to sharply increase as the driving voltage drops to sub-bandgap values, highlighting the critical role of employing low-voltage device architectures in reaching the 1350-h/1000-nit stability milestone. Finally, a flexible active-matrix PeLED display prototype is developed, showing the potential of the devices for wearable optoelectronics.