Synergistic Effect of Cation and Anion Passivation Defects and Suppression of Phase Transition Enhance the Performance and Stability of Inverted Perovskite Solar Cells

作者：Yunxin Zhang, Guodong Zhang, Haolin Lu, Hongbin Chen, Yuchuan Shao, Yifan Zheng, Fulin Sun, Bing Sun, Hao‐Li Zhang, Yongsheng Chen, Guankui Long · 发表于：Small · 年份：2025 · DOI：10.1002/smll.202503256 · 被引用次数：6 · 研究领域：Perovskite Materials and Applications、Conducting polymers and applications、Quantum Dots Synthesis And Properties

Abstract The trap states and phase instability of perovskite films harm the fabrication of high‐performance and stable perovskite solar cells (PSCs). Herein, the β ‐fluorophenylethanammonium cation ( β ‐FPEA + ) and tosylate anions (TsO − ) are employed to enhance both the performance and stability of inverted PSCs. Theoretical calculations show that β ‐FPEA + TsO − can passivate the defects at both FA‐I and Pb‐I terminals. Nuclear magnetic resonance reveals strong interactions between β ‐FPEA + TsO − and perovskites, which facilitate the fabrication of high‐quality perovskite films. During crystallization, β ‐FPEA + preferentially generates the 2D perovskite, stabilizing the black phase and passivating defects of the perovskite film. Meanwhile, the large TsO − can be extruded to the grain boundary and surface, reducing trap states and inhibiting the degradation of the perovskite film. The synergistic effect of β ‐FPEA + and TsO − passivation on defects and suppression of phase transition results in the power conversion efficiency (PCE) improved to 25.47% (vs 23.08% of the control), along with the unencapsulated device retaining 81% of initial PCE after 960 h at 85 °C in vacuum. This work provides a novel and simple strategy for designing the combination of large organic cations and non‐halogenated anions to passivate the defects and suppress phase transition, thereby achieving high performance and stable PSCs.