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 Pb2+ 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.