Interfacial Charge Modulation: An Efficient Strategy for Stable Blue Quantum‐Dot Light‐Emitting Diodes

Abstract Quantum‐dot light‐emitting diodes (QLEDs) are proposed as one of the most promising candidates for next‐generation displays, but their commercial application is seriously limited due to the poor performance of blue QLEDs (B‐QLEDs). Herein, this work uses Ti 3 C 2 T x nanosheets to tune the work function (WF) of ZnMgO and to engineer the quantum dot (QD)/electron transport layer (ETL) interface. The B‐QLEDs with ZnMgO‐Ti 3 C 2 T x hybrid ETL exhibit a maximum EQE of 15.81% and a remarkable T 50 operation lifetime of 3284 h at 100 cd m −2 . In addition to that, ultraviolet photoemission spectroscopy and density functional theory calculations both confirm that the addition of Ti 3 C 2 T x to ZnMgO can effectively tune the ZnMgO's work function, further give rise to the reduction of QD/ETL energy barrier, which finally results in the alleviation of charge accumulation at the QD/ETL interface. The findings of interface engineering by Ti 3 C 2 T x not only provide a promising strategy for the application of 2D materials in optoelectronic devices, but also pave the way to construct high‐performance light‐emitting diodes.