Transient electroluminescence in perovskite light-emitting diodes

Metal halide perovskite–based light-emitting diodes (LEDs) have shown significant potential in lighting and display applications in recent years. In situ study on the device physics of perovskite LEDs can provide us with a deeper understanding of the electronic processes involved in these promising devices, thereby facilitating further enhancements in device performance. The transient electroluminescence (TrEL) measurement is a convenient tool to probe time-resolved electronic processes in operating LEDs. To date, numerous studies have highlighted the unique advantages of TrEL measurements in understanding the device physics of perovskite LEDs, making a timely outline and recapitulation of this field essential. We summarize recent advancements in utilizing TrEL measurements to study the carrier dynamics, efficiency roll-off at ultrahigh current densities, and ion migration in perovskite LEDs. In addition, we highlight the challenges and opportunities of TrEL measurements. We aim at advancing the understanding of operational mechanisms in perovskite LEDs and further development of TrEL measurements in perovskite optoelectronic devices.