Multifunctional additive engineering with methyl 2-aminobenzoate for high-performance perovskite solar cells

Defects in perovskite solar cells (PSCs) critically hinder both device stability and power conversion efficiency (PCE). Incorporating multifunctional organic additives into the perovskite precursor offers a promising approach to overcome these limitations. Here, we report methyl 2-aminobenzoate (MA) as a novel multifunctional additive containing –COOCH 3 , –NH 2 groups, and a benzene ring. The benzene ring enhances hydrophobicity, while the ester (–COOCH 3 ) functional group, through its carbonyl oxygen and the –NH 2 group, coordinates with undercoordinated Pb 2+ ions, thereby effectively passivating Pb-related defects. Consequently, MA-modified PSCs deliver a PCE of 16.85 %, markedly higher than the 14.09 % achieved by the control devices. Moreover, the optimized devices retained 88 % of their initial efficiency after 700 h of continuous illumination at 25 °C under ambient air, underscoring their excellent long-term operational stability.