Vapor‐Assisted Nondestructive Encapsulation Strategy Enables Efficient Air‐Processed Perovskite Film‐Based Solar Cells with Entire Lifecycle Regulation

Despite the outstanding power conversion efficiency of perovskite solar cells (PSCs) achieved over the last decades, the full lifecycle from the preparation and operation to final discarding of PSCs requires careful consideration and addressing. Herein, a nondestructive encapsulation strategy is developed to realize the entire lifecycle management of air‐processed PSCs. The uniform and dense package layer on the perovskite and gold electrode is constructed by the rapid self‐adsorption and water‐triggered polymerization of 3‐mercaptopropyl‐triethoxysilan (MPTES) vapor molecules. The MPTES molecule enables improved crystallinity and multiple defect elimination to mitigate the undesirable disturbance of ambient water, reducing impurity residues and inducing oriented growth of perovskite crystals. Moreover, the encapsulation layer inhibits the FA + /I − ion loss of perovskites during the metal electrode preparation, ensuring the consistent optimization effect of films and final devices. Therefore, the air‐processed FA‐dominant PSCs deliver a superior efficiency of 26.10% with high fabrication reproducibility, maintaining 85% of its initial efficiency after 1200 h in the damp heat tests. Moreover, the end‐of‐life PSCs with nondestructive encapsulation show notably reduced toxic lead leakage, which does not cause environmental pollution and biosafety threats. This work reveals a promising route for the entire lifecycle management of air‐processed PSCs.