Scalable Ambient Fabrication of High-Performance CsPbl_2 Br Solar Cells

摘要

All-inorganic halide perovskites hold promise for emerging thin-film photovol-taics due to their excellent thermal stability. Unfortunately, it has been challenging to achieve high-quality films over large areas using scalable methods under realistic ambient conditions. Herein, we investigated the coupling between the fluid dynamics and the structural evolution during controlled film formation for ambient scalable fabrication of CsPbl_2Br perovskite films using blade coating. We simultaneously overcame the negative influences of moisture attack and the Benard-Marangoni instability in the drying ink and achieved an ideal sequential crystallization with changing halide composition during the film formation. As a result, we produced highly crystalline, uniform, and pinhole-free CsPbl_2Br films with superior photophysical and transport properties. High-performance solar cells are fabricated to achieve power conversion efficiencies (PCEs) of 14.7% for small-aperture-area (0.03 cm~2) devices and 1 2.5% for the large-aperture-area (1.0 cm~2) ones, the highest PCE reported to date for large-area all-inorganic perovskite solar cells.