| 초록 |
Metal halide perovksites are promising candidates for use in light emitting diodes(LEDs), due to their potential for colour tunable and high luminescence efficiency. While recent advances in perovskite-based light emitting diodes have resulted in external quantum efficiencies(EQEs) exceeding 12.4% for the green emitters, and 20% infrared emitters, the EQEs of the red and blue emitters still lag behind. Herein, we report the preparation and characterisation of a highly luminescent and stable suspension of methylammonium lead triiodide(CH3NH3PbI3) perovskite nanocrystals(NCs), where we sytnthesise the nanocrystals via a ligand-assisted reprecipitation technique. Through tuning the conditions,we obtain a solution of CH3NH3PbI3 NCs with a photoluminescence quantum yield exceeding 93% and tunable emission between 660nm and 705nm. We also achieved red emission at 635nm by blending the NCs with bromide salts and obtained perovskite-based LEDs with maximum electroluminescent EQE of 2.75% |
