Dihydrazide‐Mediated Crystal Engineering and Precursor Anti‐Aging for Efficient and Stable Perovskite Solar Cells and Modules

Abstract Commercialization of perovskite solar cells (PSCs) is hindered by challenges in crystallization control, long‐term operational stability, and precursor degradation. Here, a multifunctional molecule, isophthaloyl dihydrazide (BDH), is introduced to simultaneously address these issues in inverted PSCs. BDH facilitates preferential crystallization via dual‐site coordination with perovskite, resulting in improved crystallinity, suppressed non‐radiative recombination, and enhanced charge transport. Its carbonyl groups effectively passivate uncoordinated Pb 2+ ions, while the hydrazide functionality suppresses iodide oxidation in both solution and solid‐state phases. This redox‐stabilizing effect significantly extends the ambient shelf life of perovskite precursor inks to four weeks without compromising device performance. Consequently, BDH‐modified devices deliver an impressive efficiency of 25.78%, retaining 94.6% of their initial value after 1000 h of maximum power point tracking and showing no degradation across nine light‐dark cycles. Notably, the mini‐modules (aperture area of 26.78 cm 2 ) achieve a high efficiency of 22.30% and excellent stability.