High-performance perovskite light-emitting diodes based on grain boundary passivation: progress, challenges and perspectives

Metal halide perovskites are emerging as promising candidates for next-generation display and lighting technologies. In less than 10 years, the external quantum efficiency (EQE) of perovskite light-emitting diodes (PeLEDs) has skyrocketed from 0.1% to around 30%. Herein, we briefly introduce PeLEDs and summarise our group's progress in preparing PeLEDs using the strategy of grain boundary passivation. Then, we present the challenges and future outlooks toward the further development of PeLEDs. We hope that this perspective can bring informative guidance and innovative ideas to the PeLED community. Metal halide perovskites are emerging as promising candidates for next-generation display and lighting technologies.