ABSTRACT In the fabrication of n‐i‐p structured perovskite solar cells (PSCs), the perovskite layer is usually annealed in a humid environment to obtain large‐sized grains. However, the uncontrollable crystallization of complex solution components and moisture‐induced degradation result in poor crystalline quality of the perovskite layer. In this work, a novel hydrolysis‐triggered intelligent passivation of inert precursor (HTIPIP) strategy is proposed. Specifically, the inert precursor 3‐(trifluoromethyl)phenylboronic acid pinacol ester (3‐CF 3 ‐PhBpin) in the perovskite solution is in situ hydrolyzed to 3‐(trifluoromethyl) phenylboronic acid (3‐CF 3 ‐PhB(OH) 2 ), which acts as a strong Lewis acid to precisely and on‐demand passivate the defects generated during the crystallization process, while the ‐CF 3 group simultaneously provides hydrophobic protection. This strategy converts the notorious water‐induced crystallization damage of perovskite films into a chemical reaction driving force for improving the crystallization quality. Therefore, the rigid and flexible n‐i‐p perovskite solar cells fabricated based on this strategy achieved power conversion efficiencies (PCE) of 26.25% and 24.80%, respectively, and also realized significant improvements in operational stability. This work elucidates a new molecular design paradigm of actively adapting to and intelligently utilizing the processing environment, which provides critical support for the ambient‐compatible manufacturing of large‐scale perovskite photovoltaics.
Pi et al. (Mon,) studied this question.