Buried Interface Modification for High‐Performance Perovskite Light‐Emitting Diodes

Abstract Buried interface modification strategies play a critical role in advancing the development of perovskite light‐emitting diodes (PeLEDs), which is related to charge injection, perovskite crystallization, and interfacial non‐radiative recombination. Herein, 3‐aminotetrahydrofuran hydrochloride (TAH) is employed for post‐treatment of the electron transport layer (ETL). TAH modification lowers the work function of the ETL surface, which facilitates electron injection into the perovskite layers. Besides, TAH treatment modulated the perovskite crystallization dynamics, promoting the formation of discontinuous high‐quality perovskite. Meanwhile, the multifunctional TAH chemically interacted with both the perovskite and ETL, synergistically passivating vacancy and interstitial defects. Consequently, the TAH‐modified PeLEDs achieved a peak external quantum efficiency of 22.3% with a radiance of 987.4 W sr ⁻¹ m ⁻² . This work presents a viable approach to achieve superior carrier transport, precise morphology control, and effective defects passivation for improving the performance of PeLEDs.