| 초록 |
Metal halide perovskites are emerging high color-purity emitters with low material cost. However, the low electroluminescence (EL) efficiency at room temperature is a challenge that should be overcome. Here, we present efficient perovskite light-emitting diodes (PeLEDs) using various strategies to overcome the EL efficiency limitations. First, we introduced a self-organized buffer hole injection layer to reduce the hole injection barrier and block the exciton quenching at the interface. Furthermore, we found that the formation of metallic lead atoms causes strong exciton quenching, and it was prevented by finely increasing the molar proportion of methylammonium bromide (MABr) in MAPbBr3 solution. Also, we suggest that the efficiency in PeLEDs can be increased by decreasing MAPbBr3 grain sizes and consequently improving uniformity and coverage of MAPbBr3 layers. Using these strategies, a high-efficiency PeLEDs was realized (current efficiency = 42.9 cd/A). |
