講演情報
[17p-K405-4]Ligand passivation of Bi-doped Cs2SnCl6 double perovskite defects to achieve stable high luminescence
〇(D)SUJUN JI1, Boyu Zhang1, Shikai Chen1, Yongge Yang1, Feng Liu2, Shuzi Hayase1, Qing Shen1 (1.Univ. of Electro-Commun., 2.Shando Univ.)
キーワード：
Tin-based perovskite、Defect passivation、Ultrafast spectroscopy
Tin-based perovskite nanocrystals (NCs) are promising for various photonic applications due to their low toxicity, high color purity, tunable optoelectronic properties and excellent solution processability. However, surface features impact their optoelectronic properties, and surface defects remain a major obstacle to progress.1, 2 Here we developed a novel strategy to optimize Bi-doped Cs2SnCl6 nanocrystals by leveraging acetone-driven polar solvent etching for surface reconstruction (Fig. 1). The reconstructed Cs2SnCl6: Bi nanocrystals exhibit significantly improved colloidal stability, uniform monodispersity, and a more than twofold enhancement in quantum yield, achieving a remarkable value of 39%. Furthermore, this work provides valuable insights into the luminescence mechanisms of tin-based perovskites. Temperature-dependent photoluminescence (PL), ultrafast femtosecond and nanosecond transient absorption spectroscopy reveal the triplet excited-state dynamics of Bi3+ ions. Enhanced carrier lifetimes and strong photoinduced absorption (PIA) signals further confirm the successful surface passivation of the nanocrystals. Notably, the optimized Cs2SnCl6: Bi nanocrystals demonstrate excellent deep-blue emission, underscoring their potential for high-performance optoelectronic applications. These findings illuminate new pathways for advancing Sn-based perovskite nanocrystals in next-generation photonic technologies.