Minimizing Optical Energy Losses for Long-Lifetime Perovskite Light-Emitting Diodes

Regardless of the rapid advance on perovskite light-emitting diodes (PeLEDs), the lack of long-term operational stability hinders the practicality of this technology. Particularly, thermal management is indispensable to control the Joule heating induced by charge transport and parasitic re-absorption of internally confined photons. Herein, a synergetic device architecture is proposed for minimizing the optical energy losses in PeLEDs toward high efficiency and long lifetime. By adopting a carefully modified perovskite emitter in combination with an improved light outcoupling structure, red PeLEDs emitting at 666 nm achieve a peak external quantum efficiency of 21.2% and an operational half-lifetime of 4806.7 h for an initial luminance of 100 cd m^-2. The enhanced light extraction from trapped modes can efficiently reduce the driving current and suppress optical energy losses in PeLEDs, which in turn ameliorate the heat-induced device degradation during operation. This work paves the way toward high-performance PeLEDs for display and lighting applications in the future.