講演情報
[10a-PB1-23]Effect of Alkyl Substituent Position in Pyridinium Ionic Liquids on the Stability of Perovskite Solar Cells
〇(P)Jaseela Palasheriithikkal1, Masahiro Nakano1, Hidetaka Yamada1, Shahiduzzaman Mohammed1, Tetsuya Taima1 (1.Kanazawa University)
キーワード：
Perovskite solar cell、Ionic liquid additive、High stability
Poor environmental stability remains a key challenge for the commercialization of perovskite solar cells (PSCs). In this work, three positional isomers of pyridinium-based ionic liquids (ILs)—1-butyl-2-methylpyridinium chloride (2-BMPyCl), 1-butyl-3-methylpyridinium chloride (3-BMPyCl), and 1-butyl-4-methylpyridinium chloride (4-BMPyCl)—were incorporated into CsFAMA perovskite precursor solutions to investigate the relationship between IL molecular structure, perovskite film properties, and device stability. All IL-treated films exhibited larger grain sizes, reduced defects, and enhanced crystallinity compared to the pristine film. Among them, 2-BMPyCl produced the largest grains owing to its higher viscosity, which retarded crystallization and promoted grain growth. PSCs containing pyridinium-based ILs showed significantly improved ambient stability (~45% RH). Notably, the 4-BMPyCl-treated device retained 85% of its initial power conversion efficiency (PCE) after 160 days, outperforming devices treated with 3-BMPyCl (77%) and 2-BMPyCl (71%). The superior stability of 4-BMPyCl is attributed to its greater hydrophobicity and lower steric hindrance, enabling more effective defect passivation and moisture resistance. These findings demonstrate that the molecular structure of pyridinium-based ILs plays a crucial role in regulating perovskite crystallization and enhancing the long-term stability of PSCs.