| 초록 |
Metal halide perovskite nanocrystals (PNCs) are regarded as promising emitters due to their outstanding optical properties(PLQY, color purity). Such properties have led to rapid progress in perovskite light-emitting diodes (PeLEDs). To further improve electroluminescence efficiency, (1) increasing the radiative recombination rate and (2) lowering the non-radiative recombination rate should be considered. Here, we report a one-dopant alloying strategy that confines more electrons and holes and reduces non-radiative recombination. Doping of guanidinium into formamidinium lead bromide PNCs yields limited bulk solubility while creating an entropy-stabilized phase in the PNCs and leading to smaller PNCs with more carrier confinement. To reduce extra defects, 1,3,5-tris(bromomethyl)-2,4,6-triethylbenzene was applied as a defect healing agent. Through these defect suppression strategies, efficient PeLEDs that have current efficiency of 108 cdA−1 (EQE of 23.4%) are achieved. |
