Self-Assembled Monolayers for Perovskite Solar Cells: Molecular Design and Chemical Synthesis

Self-assembled monolayers (SAMs) have been a game-changer for perovskite solar cells (PSCs), significantly boosting their power conversion efficiency (PCE) to 27% in recent years. This breakthrough has garnered unprecedented attention, leading to significant advancements in the design and synthesis of SAM molecules (SAMols). Additionally, SAMs hold significant promise in addressing the lifetime of PSCs and facilitating their commercialization in terms of diversity, flexibility, and multifunctionality. To date, despite the development of numerous types of SAMols, challenges remain in designing and synthesizing optimal SAMols and achieving ultrastable devices that maintain outstanding PCEs. In this review, we systematically present recent advances in the design of SAMols, focusing on representative examples that have been employed in PSCs. Subsequently, a comprehensive overview of various synthetic pathways for these SAMols is provided for screening the most suitable synthesis method for target SAMols. Finally, challenges and potential opportunities for PSCs applications are highlighted.