High-quality perovskite quantum dot light emitting diode

Abstract

Perovskite quantum dot-based Light-emitting diodes (PQDLEDs) attracted considerable attention because of the remarkable properties of the perovskite quantum dots (PQDs): exciton confinement, high quantum yield, and adjustable color. In our research, to prohibit fluorescence quenching dots which is caused by the connection of the PQDs and hole injection material into the emissive layer and hole injection layer, poly [(9,9- dioctylfluorenyl-2,7-diyl)-co-(4,4’-(N-(pbutylphenyl)) diphenylamine)] (TFB) is utilized which can decrease the hole injection barrier. As the TFB layer is prepared by a spin-coating setup, the layer can be managed by controlling the concentration of the TFB precursor solution and the rotational speed for spin-coating the TFB solution. Therefore, in this study, we do both of them to reach a high-quality perovskite quantum dot light emitting diode. Also, we fabricate a control device (without a TFB layer) to compare the luminescence results. Results show that for fabricated PQDLEDs, turn-on voltage decreases from 3.01 V (for the device without TFB) to 2.2 V (for the optimized device). Besides, for the best-optimized PQDLED, it is shown that the maximum brightness is about 4550 cd m−2, maximum external quantum efficiency (EQE) versus luminance is 0.153%, and maximum current efficiency is about 0.5 cd A−1.