Improved performance of CsPbBr3 quantum-dot light-emitting diodes by bottom interface modification

Improving Perovskite Green Quantum Dot Light-Emitting Diode Performance by Hole Interface Buffer Layers

“…In general, compared to polycrystalline perovskite films, thinner perovskite QD films will achieve higher EQE due to enhanced light outcoupling. , However, the QD films bring a series of charge injection problems. − Fluorescence quenching of the perovskite QD thin film caused by imbalance charge injection is a reason for a low EQE of perovskite QLEDs, which also affects the operation stability of devices. − In addition, due to the highly sensitive surface and complex interface environment of perovskite QD films, QD films will inevitably produce a large number of defects. These defects are located at the interface between the QD layers and the carrier transport layers, which will form a large number of nonradiative recombination centers, seriously affect the injection and transmission of carriers, and reduce the efficiency of devices. − Interface engineering could be a simple and effective way to improve the hole interface; many types of research are dedicated to interface engineering to adjust the charge injection and fluorescence quenching of QLEDs. − At present, most of the related works focus on the passivation of the electron interfaces of QD layers. − Comparatively, the hole surface interface passivation of the QD films is equally important. Due to the strong hole-transporting ability of PTAA, an effective hole-transporting material, quantum dot (QD) films are prone to be charged, which leads to the imbalance of charge injection and the increase of nonradiative recombination .…”