Understanding the Synergistic Effect of Device Architecture Design toward Efficient Perovskite Light‐Emitting Diodes Using Interfacial Layer Engineering

Abstract Metal halide perovskite (MHP) light‐emitting diodes (LEDs) have been widely studied and have been reached to > 20% external quantum efficiency, owing to their attractive characteristics (e.g., solution processability, tunable bandgap and extremely high color purity, high mobility). During the rapid development of perovskite light‐emitting diodes (PeLEDs), modifying the device architecture has been widely studied as well as improving the crystal quality of MHP to achieve near‐unity photoluminescence quantum yield. However, efforts in device architecture engineering have received less attention despite their significance. Here, strategies are reviewed to enhance the efficiency of PeLEDs in terms of the device engineering by interfacial charge injection/transport, exciton‐quenching blocking, and defect passivation layers for enhancing radiative electron–hole recombination. Strategies are systematically classified for each layer in PeLEDs and discussed the synergetic effect between different strategies. Perspective is also provided on future research on PeLEDs focusing on their architecture.