Zwitterionic-Surfactant-Assisted Room-Temperature Coating of Efficient Perovskite Solar Cells

Summary With amazing progress in the state-of-the-art perovskite solar cells (PSCs) fabricated by laboratory-scale spin-coating methods, upscaling the PSCs via printing friendly techniques is becoming more and more important toward the future deployment of large-scale and stable perovskite modules. Here, we demonstrate the room-temperature meniscus coating of high-quality perovskite films incorporated with a multifunctional sulfobetaine-based zwitterionic surfactant. Systematic in situ studies uncover the perovskite crystallization pathway and emphasize the surfactant's synergistic role in film construction, crystallization kinetics modulation, defect passivation, and moisture barrier protection. This strategy is applicable across perovskite compositions and device architectures with the enhanced power conversion efficiencies up to 22%. Upscaling the device area to 0.8 cm2 has negligible deterioration in the performance. This represents one of the highest records for the upscaling coated PSCs, not limited in room-temperature coated PSCs. In addition, this approach significantly improves the stability of perovskite films and devices under different aging conditions.