The Rise of Perovskite Light-Emitting Diodes.

Recently, metal halide perovskite materials have attracted great interest in both photovoltaic and electroluminescent devices. The external quantum efficiency of the perovskite light-emitting diodes (pero-LEDs) has grown to over 20% within four years, and the operational lifetime has been improved to tens of hours. These achievements make pero-LEDs very promising technology in solid lighting and displays. In this Perspective, we first give a general introduction of the pero-LEDs; we then discuss various pero-LEDs with different cell configurations and perovskite emitting structures; to conclude, we propose some efficiency improvement strategies and development opportunities of pero-LEDs. Provided that we can continually improve efficiency and operational lifetime of pero-LEDs, we can make them more and more compatible with other mature technologies, like organic LEDs and inorganic LEDs, and then finally realize their practical application in daily life.