Zhang Yiyue, Chen Jim Jui-Kai, Fron Eduard, Bazylevska Anastasiia, Wang Peiran, Sternemann Christian, Paulus Michael, De Feyter Steven, Roeffaers Maarten, Debroye Elke, Hofkens Johan, Pradhan Bapi
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, Leuven 3001, Belgium.
KU Leuven Core Facility for Advanced Spectroscopy, KU Leuven, Celestijnenlaan 200F, Leuven 3001, Belgium.
J Phys Chem Lett. 2025 Aug 14;16(32):8353-8362. doi: 10.1021/acs.jpclett.5c01860. Epub 2025 Aug 7.
Metal halide perovskites constitute a promising area of research for application in light-emitting diodes (LEDs), given the successful demonstration of high external quantum efficiency (EQE) devices across the visible to the near-infrared window. Nevertheless, the ionic crystal structure, significantly impacted by internal defects and ionic migration, poses a challenge to the long-term stability of perovskite materials. This limitation stands as a pivotal hurdle impeding further commercialization of perovskite LEDs (PeLEDs). Two-dimensional (2D) perovskite-based materials strive to enhance the operational stability of PeLED devices by refining the crystal structure and passivating the film defects. To this end, we have successfully developed high-quality 2D perovskite thin films using 1,4-butanediammonium (BDA) and methylammonium as alternating cations in the interlayer space (ACI) for efficient LEDs with improved operational stability. Our best-performing device demonstrates an EQE of 4.3% at a high current density () of 130 mA/cm and remains above 3.3% for a up to 510 mA/cm, leading to a high radiance of 138 W/Sr·m when driven at 6 V. More importantly, this device shows impressive operational stability, retaining ∼80% of its initial performance operating at 25 mA/cm for 9 h. The utilization of ACI perovskites in PeLEDs demonstrates their potential for balancing both high stability and high efficiency.
鉴于在可见光到近红外窗口范围内成功展示了具有高外量子效率（EQE）的器件，金属卤化物钙钛矿成为发光二极管（LED）应用中一个有前景的研究领域。然而，离子晶体结构受到内部缺陷和离子迁移的显著影响，这对钙钛矿材料的长期稳定性构成了挑战。这一限制是阻碍钙钛矿LED（PeLED）进一步商业化的关键障碍。基于二维（2D）钙钛矿的材料致力于通过优化晶体结构和钝化薄膜缺陷来提高PeLED器件的运行稳定性。为此，我们成功地使用1,4 - 丁二铵（BDA）和甲铵作为层间空间（ACI）中的交替阳离子，开发出了高质量的2D钙钛矿薄膜，用于具有更高运行稳定性的高效LED。我们性能最佳的器件在130 mA/cm的高电流密度下展示出4.3%的EQE，并且在高达510 mA/cm的电流密度下保持在3.3%以上，在6 V驱动时产生138 W/Sr·m的高辐射亮度。更重要的是，该器件显示出令人印象深刻的运行稳定性，在25 mA/cm的电流下运行9小时后仍保持其初始性能的约80%。在PeLED中使用ACI钙钛矿证明了它们在平衡高稳定性和高效率方面的潜力。
