Multifunctional Additives to Enhanced Perovskite Solar Cell Performance

Perovskite solar cells (PSCs) have been developing rapidly in recent years, in which the choice of additives plays a crucial role. Herein, a new small molecule is introduced named 5‐ADI with amino and carbonyl groups as an additive for perovskite. Specifically, the carbonyl group in 5‐ADI can interact with undercoordinated Pb 2+ to passivate the perovskite defects. Moreover, the amino group can effectively immobilize I − atoms and inhibit ion migration, and it can synergistically passivate defects and improve photovoltaic performance. Meanwhile, the 5‐ADI treatment makes energy levels match well. Consequently, high‐quality perovskite film with fewer defects is produced due to 5‐ADI treatment improves the crystallinity of perovskite. The device fabricated with 5‐ADI additive achieves a power conversion efficiency of 22.42%. Besides, 5‐ADI can act as a barrier against water to promote perovskite moisture stability. In general, a superior strategy for defect passivation in PSCs is provided.