Hydrofluoroethers as orthogonal solvents for all-solution processed perovskite quantum-dot light-emitting diodes

Abstract

Recently, metal halide perovskite quantum dots (QDs) have been becoming a kind of promising efficient luminescent material and drawn remarkable attention in the development of light-emitting devices. However, during the fabrication process of perovskite QDs based light emitting diodes (Pe-QLED), the vacuum processing is necessary for constructing of perovskite QDs/charge transport layer (CTL) structure. Taking the large-scale production into consideration, the all-solution processed Pe-QLED have great potential, but remain great challenge. Herein, we show that by employing hydrofluoroethers (such as HFE 7100) as the orthogonal solvent, the perovskite QDs/CTL multilayer structure can be effectively obtained via solution process, thus promoting the successful fabrication of all-solution Pe-QLED. Through the surface fluorous ligand modification, ZnO nanoparticles (NPs) are directly dispersed in HFE 7100 and used for solution processed electron transport layer. As the result, all-solution processed CsPbBr3 Pe-QLEDs have been realized with the performance of a luminance of 1661 cd/m2, a peak EQE of 0.37%, and a peak CE of 0.72 cd/A. These results indicate that our strategy is highly effective in the development of high-performance all-solution processed perovskite based optoelectronic devices.