Perovskite Solar Cells Enabled by the Synergy of Chlorine Additive and Scalable Rapid Photonic Annealing of Multiple Stacking Layers

ABSTRACT Perovskite solar cells (PSCs) have gained significant attention due to their impressive power conversion efficiencies. However, developing rapid fabrication techniques for commercially feasible production of PSCs with high stability and efficiency requires more investigation. Also, as a feasible approach, additive strategy plays a crucial role in enhancing crystallinity and reducing defects of perovskite films, thereby improving the device performance. Herein, we explored the synergy of rapid UV‐LED annealing of multiple stacked layers while incorporating chlorine‐containing additive to enhance the morphology, crystallinity, and optoelectronic properties of perovskite absorber and demonstrated significant improvement of overall PSC performance, including both efficiency and stability. Specifically, chlorine incorporation leads to larger grain sizes, reduced defects and recombinations, and more efficient perovskite conversion with rapid UV‐LED annealing. The best all‐rapid photonic annealed (all‐RPA) PSC device with addition of chlorine‐containing additive demonstrates a PCE of 21.7% and retains over 80% of the initial PCE after 1000 h, which is the highest PCE ever reported on traditional MAPbI 3 ‐based PSCs fabricated with all kinds of optical annealing schemes. This work sheds light on the role of synergistic effects of UVA‐LED annealing and chlorine incorporation and paves the way for large‐scale manufacturing of perovskite‐based photovoltaics by using rapid and energy‐efficient UV‐LED photonic annealing.