Li Chenglong, Zeng Xiankan, Pan Lunyao, Chen Yongjian, Mu Maolin, Shen Di, Wang Xinning, Yang Weiqing, Li Wen
Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China.
Research Institute of Frontier Science, Southwest Jiaotong University, Chengdu 610031, PR China.
ACS Appl Mater Interfaces. 2025 Oct 1;17(39):55045-55053. doi: 10.1021/acsami.5c11514. Epub 2025 Sep 16.
Perovskite light-emitting diodes (PeLEDs) have emerged as promising candidates for next-generation displays, yet blue PeLEDs significantly lag behind their green/red counterparts. The inferior performance of blue PeLEDs arises from two principal challenges: trap-assisted nonradiative recombination and halide ion migration. Herein, we introduce a multifunctional additive strategy utilizing hexamethylene diisocyanate (HDI) to synergistically address these limitations in blue mixed-halide PeLEDs. The N═C═O functional group in HDI demonstrates dual functionality: (1) selective coordination with the unsaturated lead sites effectively passivates defects while filling halide vacancies, and (2) reduced halide vacancy suppresses ion migration and ultimately achieves stabilization of the perovskite lattice. This approach obtained blue perovskite films with an enhanced photoluminescence quantum yield (PLQY) and reduced defect density. Comprehensive capacitance-voltage characterization reveals that HDI-optimized blue PeLEDs exhibit enhanced carrier transport efficiency and suppressed interface carrier accumulation. Resulting blue PeLEDs achieve a peak external quantum efficiency of 9.56% and a stable electroluminescence peak at 488 nm, demonstrating a maximum luminance of 3321 cd m. This work establishes an effective strategy for high-quality blue PeLEDs, accelerating advancement toward the practical implementation of high-performance blue PeLEDs.
钙钛矿发光二极管（PeLEDs）已成为下一代显示器的有力候选者，然而蓝色PeLEDs明显落后于绿色/红色同类产品。蓝色PeLEDs性能较差源于两个主要挑战：陷阱辅助非辐射复合和卤离子迁移。在此，我们引入一种利用六亚甲基二异氰酸酯（HDI）的多功能添加剂策略，以协同解决蓝色混合卤化物PeLEDs中的这些限制。HDI中的N═C═O官能团具有双重功能：（1）与不饱和铅位点选择性配位，有效钝化缺陷并填充卤化物空位；（2）减少卤化物空位可抑制离子迁移并最终实现钙钛矿晶格的稳定。这种方法获得了具有增强的光致发光量子产率（PLQY）和降低的缺陷密度的蓝色钙钛矿薄膜。综合电容 - 电压表征表明，HDI优化的蓝色PeLEDs表现出增强的载流子传输效率和抑制的界面载流子积累。由此产生的蓝色PeLEDs实现了9.56%的峰值外量子效率和在488nm处的稳定电致发光峰值，最大亮度为3321 cd m。这项工作为高质量蓝色PeLEDs建立了一种有效策略，加速了向高性能蓝色PeLEDs实际应用的推进。
