This study introduces a novel approach to fabricating large‐area perovskite active layers for carbon‐based perovskite solar cells (C‐PSCs) by leveraging electrodeposition, a low‐cost, scalable and yet underexplored processing route. The work focuses on the synthesis and comprehensive characterization of methylammonium lead iodide (MAPbI 3 ) perovskites incorporating a low bismuth additive content (0.85 mol%), representing the first systematic investigation of bismuth‐assisted MAPbI 3 films produced via electrodeposition. Despite the very low bismuth concentration, clear structure–property relationships were established by optimizing the conversion time, directly correlating processing conditions with optical, structural, and photovoltaic (PV) performance. A central innovation lies in the incorporation of bismuth, which not only modifies the perovskite crystallization but also markedly improves environmental stability. Long‐term aging tests under harsh conditions (90% RH, 30°C, 1000 h) revealed that these mixed perovskites maintain their microstructure and properties far better than MAPbI 3 . The devices fabricated with perovskites containing 0.85% Bi retain up to 70% of their initial efficiency even without encapsulation, compared to only 35% for MAPbI 3 ‐based controls. These results demonstrate the great potential of bismuth‐assisted electrodeposition for enabling durable, scalable perovskite PVs and offer a promising pathway toward sustainable C‐PSC manufacturing.
Lavoipierre et al. (Mon,) studied this question.