Synergetic Dual‐Additive Strategy for Regulating Crystallization and Defect Passivation of Perovskite Nanograin Toward Efficient Light‐Emitting Diodes

作者：Yue Liang, Dengliang Zhang, Guangrong Jin, Bufan Yu, Xingxing Duan, Kaiwang Chen, Jiacheng Liu, Wei Hong, Lei Wang, Guichuan Xing, Jiangshan Chen, Dongge Ma · 发表于：Advanced Optical Materials · 年份：2024 · DOI：10.1002/adom.202402290 · 被引用次数：11 · 研究领域：Perovskite Materials and Applications、Quantum Dots Synthesis And Properties、ZnO doping and properties

Abstract Perovskite nanograins with a dimension larger than the Bohr exciton diameter have significant advantages in achieving high‐performance light‐emitting diodes (LEDs) due to their bandgap uniformity and strong charge confinement effect. However, perovskite nanograin films prepared by the solution spin‐coating method are prone to produce massive defects due to the fast crystallization rate, leading to severe nonradiative recombination that greatly detracts the performance of LEDs. Therefore, regulating crystallization and minimizing defects plays a crucial role in the development of perovskite nanograins for high‐performance LEDs. Herein, a simple dual‐additive strategy is reported to manipulate the growth of high‐quality CsPbBr 3 ‐based nanograin films. A multifunctional additive 5‐aminovaleric acid (5AVA) is introduced to slow down the crystallization rate of CsPbBr 3 , followed by the further addition of triphenylphosphine oxide (TPPO) to achieve effective synergistic passivation of defects, which can significantly enhance radiative recombination rate and reduce defects‐induced nonradiative recombination. Ultimately, based on the 5AVA and TPPO co‐modified CsPbBr 3 nanograins, the perovskite LEDs are fabricated achieving a maximum external quantum efficiency (EQE) of 20.95% and an average EQE of approaching 20%, demonstrating excellent reproducibility. This work provides new insight into the crystallization regulation and defect passivation of perovskite nanograins and...