Enhancing the Performance and Stability of Perovskite Solar Cells through the Introduction of the Multifunctional Additive 5‐Amino‐2‐Fluorobenzoic Acid

As the evolution of energy resources continues, perovskite solar cells (PSCs) are gaining increasing attention from researchers and are emerging as strong competitors to silicon‐based solar cells. However, due to the preparation process, defects are inevitable and have a significant impact on the efficiency and stability of PSCs. Therefore, it is essential to explore effective passivation strategies to minimize nonradiative recombination, enhance carrier mobility, and improve the overall photovoltaic performance of these cells. Herein, 5‐amino‐2‐fluorobenzoic acid (5‐AFA) is incorporated into the perovskite precursor solution as an additive. The aim is to investigate the passivation mechanism of the composite, which involves multifunctional groups such as –COOH, –NH 2 , and –F. The results demonstrate that this additive effectively passivates the defects, suppresses nonradiative recombination, slows down the crystallization process, improves film crystallinity, and ultimately enhances both the efficiency and stability of the PSCs. Specifically, the passivated PSCs achieve an impressive power conversion efficiency of 20.37%. These cells also exhibit remarkable stability with the unencapsulated devices maintaining an initial efficiency of 79% even after 700 h in an indoor environment. These findings highlight the successful application of the 5‐AFA additive in enhancing the performance and durability of PSCs.