Interfacial Regulation toward Efficient CsPbBr₃ Quantum Dot-Based Inverted Perovskite Light-Emitting Diodes

Inverted perovskite light-emitting diodes (PeLEDs) based on quantum dots (QDs) are some of the most promising candidates for next-generation lighting and display applications. Due to the strong fluorescence quenching caused by zinc oxide, high performance in such inverted devices remains challenging. Here, we report an efficient inverted green CsPbBr₃ QDs LED using an emitting buffer layer. Ultrathin CsPbBr₃ QD emitters act as the buffer layer to reduce the interface luminescence quenching reaction at the ZnO/upper emitting layer interface, increasing the probability of exciton recombination within the emissive layer and regulating the charge transport, leading to effective carrier recombination. The resulting device exhibits an external quantum efficiency of 13.1%, enhanced by about 4.7 times compared with that without a buffer layer device. This work provides a path to fabricating high-performance inverted PeLEDs.