An Air Knife-Assisted Recrystallization Method for Ambient-Process Planar Perovskite Solar Cells and Its Dim-Light Harvesting

Abstract

The photovoltaic performance of perovskite solar cells is highly dependent on the control of morphology and crystallization of perovskite film, which usually requires a controlled atmosphere. Therefore, fully ambient fabrication is a desired technology for the development of perovskite solar cells toward real production. Here, an air‐knife assisted recrystallization method is reported, based on a simple bath‐immersion to prepare high‐quality perovskite absorbers. The resulted film shows a strong crystallinity with pure domains and low trap‐state density, which contribute to the device performance and stability. The proposed method can operate in a wide process window, such as variable relative humidity and bath‐immersion conditions, demonstrating a power conversion efficiency over 19% and 27% under 1 sun and 500–2000 lux dim‐light illumination respectively, which is among the highest performance of ambient‐process perovskite solar cells.