Multiple Host Materials Engineering Boosts the Light-Emitting Diodes Performance of Metal Nanocluster

Metal nanoclusters (NCs) with a metal core consisting of a few to hundreds of metal atoms that are protected by organic ligands, can be regarded as the candidate materials for the emission material of the light-emitting diode (LED), due to their excellent properties, such as high electrical conductivity, high photoluminescence quantum yield, and good solution processability, etc. However, unbalanced carrier transport, inadequate energy transfer, and poor film-forming quality hinder the development of NC-based LEDs (NC-LEDs). In this regard, we employed a multiple host system composed of an exciplex system with electron transport material 2,2'-(1,3-Phenylene)-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole] (OXD-7), providing an efficient energy transfer, constructing the flatness films, and balancing carrier transport. As a result, the modified NC-LED achieved a maximum brightness of 4932 cd m(-2) and a peak external quantum efficiency (EQE) of 5.29%.