Li Zejian, Wang Jiaqi, Chi Shurui, Lin Kebin, Zhang Wenchao, He Chenlu
School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu 611731, P. R. China.
ACS Nano. 2024 Dec 24;18(51):34962-34970. doi: 10.1021/acsnano.4c13260. Epub 2024 Dec 11.
Chiral organic-inorganic hybrid perovskite nanocrystals have gained attention as promising materials for circularly polarized luminescence emission, owing to their high photoluminescence efficiency and superior charge-carrier mobility. However, achieving circularly polarized electroluminescence (CPEL) from mixed-phase perovskite nanocrystals remains a significant challenge. We present bichiral formamidinium lead bromide (FAPbBr) nanocrystals that achieve room-temperature circularly polarized light-emitting diodes (LEDs) via a synergistic effect between a chiral interior spacer (methylbenzylamine cation, MBA) and a chiral surface ligand (camphorsulfonic acid, CSA). The incorporation of MBA induces chiral crystal lattices, while CSA ligands, featuring sulfonate groups, effectively passivate defects, suppress exciton spin-flip, and enhance conductivity. The resulting circularly polarized LEDs exhibit an enhanced electroluminescence asymmetry factor () of ∼2 × 10, along with an external quantum efficiency (EQE) of 3.1%. These bichiral nanocrystals represent a significant advancement in luminescence efficiency and enantioselectivity, indicating their potential for next-generation chiroptoelectronic applications.
手性有机-无机杂化钙钛矿纳米晶体因其高光致发光效率和优异的电荷载流子迁移率，作为圆偏振发光发射的有前景材料而受到关注。然而，从混合相钙钛矿纳米晶体实现圆偏振电致发光（CPEL）仍然是一个重大挑战。我们展示了双手性甲脒铅溴化物（FAPbBr）纳米晶体，其通过手性内部间隔基（甲基苄胺阳离子，MBA）和手性表面配体（樟脑磺酸，CSA）之间的协同效应实现了室温圆偏振发光二极管（LED）。MBA的掺入诱导了手性晶格，而具有磺酸根基团的CSA配体有效地钝化缺陷、抑制激子自旋翻转并提高导电性。所得的圆偏振LED表现出增强的电致发光不对称因子（）约为2×10，以及3.1%的外量子效率（EQE）。这些双手性纳米晶体在发光效率和对映选择性方面取得了重大进展，表明它们在下一代手性光电子应用中的潜力。
