Interfacial modification via aniline molecules with multiple active sites for performance enhancement of n–i–p perovskite solar cells

Passivation of the buried interface benefits the poor crystallization of perovskite films caused by defects, improves the interface contact with the electron transport layer and inhibits severe non-radiative recombination. The 4′-methoxy-2′-nitroacetanilide (ANE) molecule has a variety of active sites, including CO, C–O–C and NOO, and is promising to be used as an interface modifier in perovskite solar cells. Our research confirms that ANE could reduce defects by forming chemical interactions with both SnO2 and the perovskite layer. The quality of the perovskite and SnO2 is enhanced with suppressed non-radiative recombination. Finally, the power conversion efficiency (PCE) of a champion device is improved to 22.63%. The target device retains 92% of its initial PCE (22.27%) after 1200 hour storage in the air. This study provides a key to designing and screening multifunctional passivators to improve the performance of PSCs.