Achieving Fully Blade-Coated Ambient-Processed Perovskite Solar Cells by Controlling the Blade-Coater Temperature

The state-of-the-art solution-processed perovskite solar cells (PVSCs) have reached the compelling power conversion efficiency (PCE) of 22.1%, comparable with most of the current single-junction nonconcentrated commercialized solar cells. However, the development of scalable printing and coating techniques compatible with the fabrication of PVSCs in ambient conditions still lags behind, due to the following two reasons: 1) The ambient oxygen and moisture significantly degrade the characteristics and functionality of the perovskite films, and 2) most of the research groups focus on the lab-scale spin-coating, hindering gaining knowledge and experience required to understand and employ scalable methods. In this paper, we fabricated all layers of the PVSCs, except for the back contact, by scalable blade-coating method, performed in ambient conditions, and achieved a high PCE of 11.1%, with superior device stability. Through selecting a nonhalide source and strong reducing agent, we alleviated the oxidation problem in ambient conditions. Moreover, we found an optimized blade-coater substrate temperature of 125 degrees C, which can yield micrometer-scale perovskite domain size created by thermocapillary Marangoni motion, high crystallinity, large absorption, and prolonged carrier lifetime. These results are promising for manufacturing PVSCs in high volume and in ambient conditions.