Phthalide and 1‐Iodooctadecane Synergistic Optimization for Highly Efficient and Stable Perovskite Solar Cells
Xuping Liu, Jihuai Wu, Chunyan Wang, Yuqian Yang, Deng Wang, Guodong Li, Yitian Du, Yuan Xu, Lei Zhang, Tingting Zhang, Lan Zhang
Abstract
Abstract The carrier non‐radiative recombination and instability of device caused by the inherent defects are main factors limiting development of perovskite solar cells (PSCs). During the fabrication process of a PSC device, perovskite films often produce Pb 0 and I 0 defects. This paper reports a strategy for synergistic optimization of perovskite films by defects passivation and surface modification. The doping of phthalide (PT) in the Pb‐rich (CH(NH 2 ) 2 ) 1−x (CH 3 NH 3 ) x PbI 3 film can passivate lead cation defects, and the modification of 1‐iodooctadecane (1‐IO) can reduce halogen anion defects and improve stability of PSCs owing to its hydrophobicity. The PT and 1‐IO optimized device achieves a power conversion efficiency (PCE) of 22.27%. The optimized PSCs remain 93.2% of the initial PCE when placed in air environment (relative humidity of 10%, 25 °C) more than 70 days. The PT and 1‐IO synergistic optimization provides a novel strategy for improving the performance and stability of PSCs.