Suppressing Auger Recombination of Perovskite Quantum Dots for Efficient Pure-Blue-Light-Emitting Diodes

作者：Chenghao Bi, Zhiwei Yao, Jingcong Hu, Xingyu Wang, Mengqi Zhang, Shuyu Tian, Aqiang Liu, Yue Lu, Nora H. de Leeuw, Manling Sui, Jianjun Tian · 发表于：ACS Energy Letters · 年份：2022 · DOI：10.1021/acsenergylett.2c02613 · 被引用次数：129 · 研究领域：Perovskite Materials and Applications、Quantum Dots Synthesis And Properties、Organic Light-Emitting Diodes Research

It is a big challenge to achieve pure-blue (≤470 nm) perovskite light-emitting diodes (PeLEDs) with high efficiency and stability. Here, we report pure-blue (electroluminescence at 469 nm) PeLEDs with a full width at half-maximum of 21 nm, high external quantum efficiency of 10.3%, luminance of 12 060 cd m –2, and continuous operation half-life of 25 h, representing the state-of-the-art performance. This design is based on strongly quantum confined CsPbBr 3 quantum dots (QDs) with suppression of Auger recombination, which was enabled by inorganic ligands, replacing initial organic ligands on the QDs. The inorganic ligand acts as a “capacitor” to alleviate the charge accumulation and reduce the exciton binding energy of the QDs, which suppresses the Auger recombination, resulting in much lower efficiency roll-off of PeLEDs. Thus, the devices maintain high efficiency (>10%) at high luminance (>2000 cd m –2 ), which is of considerable significance for the display application.