Self-assembled monolayers as hole selective contacts for perovskite solar cells: experiment versus simulations

Recent advances in the performance of perovskite solar cells (PSCs) have been strongly linked to advancements in interfacial engineering and the development of charge-selective contact.Self-assembled monolayers (SAMs) play an important role in inverted PSCs due to their distinctive and versatile ability to manipulate chemical and physical interface properties.Here we compared the dipole moments and energy levels of (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz), (4-(3,6-Dimethyl-9H-carbazol-9yl)butyl)phosphonic acid (Me-4PACz), (4-(3,6-Dimethoxy-9H-carbazol-9-yl)butyl)phosphonic acid (MeO-4PACz), and (2-(3,7-Dibromo-10H-phenothiazin-10-yl)ethyl)phosphonic acid (Br-2EPT) molecules and their impact on the energy conversion of PSC devices.Additionally, we simulated the dipole moment and surface charge effect device behavior to support our hypothesis.Finally, we observed that the fill factor behavior in both devices and simulations exhibited a similar trend, which correlated with the dipole moment of SAMs.