All-inorganic CsPbBr₃ perovskite quantum dots (QDs) hold great promise as candidate materials for next-generation electroluminescent displays owing to their excellent optoelectronic properties. However, the long insulating ligands on the surface of CsPbBr₃ QDs originating from the synthesis process hinder the fabrication of high-performance optoelectronic devices. Herein, an efficient ligand-exchange route is proposed with the use of perovskite-precursor-based halide ligands, including a series of phenalkylammonium bromides with a π-conjugation benzene ring and different branch lengths. Based on the ligand-exchange method, the conductivity of the CsPbBr₃ QD layer is significantly improved owing to ligand shortening and the insertion of the π-conjugation benzene ring. As a result, high brightness (up to 12,650 cd/m²) and low turn-on voltage (as low as 2.66 V) can be realized in CsPbBr₃ QD light-emitting diodes (QLEDs), leading to dramatic improvements in device performance with a current efficiency of 13.43 cd/A, power efficiency of 12.05 lm/W, and external quantum efficiency of 4.33%.

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由于其优异的光电性能，全无机CsPbBr ₃钙钛矿量子点（QD）有望成为下一代电致发光显示器的候选材料。然而，源自合成过程的CsPbBr ₃ QDs表面长的绝缘配体阻碍了高性能光电器件的制造。在本文中，提出了使用钙钛矿前体基卤化物配体的有效配体交换途径，包括一系列具有π-共轭苯环和不同支链长度的苯烷基溴化苯铵。基于配体交换法，CsPbBr ₃的电导率由于配体缩短和π共轭苯环的插入，QD层得到了显着改善。结果，可以在CsPbBr ₃ QD发光二极管（QLED）中实现高亮度（高达12,650 cd / m ²）和低导通电压（低至2.66 V ），从而极大地改善了器件性能。电流效率为13.43 cd / A，功率效率为12.05 lm / W，外部量子效率为4.33％。

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