2213454-59-0

benzimidazole hydroiodide
Purity: ≥99.0%
Synonyms: 1H-benzo[d]imidazole hydrogen iodide, BII
CAS number: 2213454-59-0
Molecular formula: C7H7IN2
Molecular weight: 246.05

Owing to the durable environmental stability and tunable photophysical properties of the two-dimensional Ruddlesden-Popper (2D RP) perovskite, it has a great potential in stable perovskite solar cells (pero-SCs). However, almost efficient 2D RP pero-SCs are prepared by the hot-casting or anti-solvent assisted spin-coating method, which greatly limits their applications. Herein, a multifunctional strategy through introducing a novel organic salt, benzimidazolium iodide (BnI), as a spacer and KI as an additive is reported to successfully fabricate a high-quality Bn-based 2D RP perovskite film in the hot-casting and anti-solvent free spin-coating method. The entire conjugated backbone of benzimidazolium is expected to enhance charge carrier transport within the 2D RP perovskite film. And KI can lead to a preferred orientation and less defects in the 2D RP perovskite film. Then, a maximum power conversion efficiency (PCE) of 15.12% is obtained, which is the highest performance for 2D RP perovskite devices without the hot-casting or anti-solvent method. The unsealed device maintains 92.1% of its original performance when kept in air (40-45% relative humidity) for 720 h and 87.9% of the initial performance after 528 h of heating at 85 °C.