Coordination force-led multifunctional molecules for efficient perovskite solar cells

Abstract

Perovskite solar cells (PSCs) have garnered great interest as an innovative and high-performance photovoltaic technology, and their maximum photovoltaic conversion efficiency (PCE) has exceeded 26%, approaching the theoretical maximum Shockley–Queisser limit PCE of approximately 33%. In this process of enhancing the performance of PSCs, various multifunctional molecules, which contain multiple functional groups, have been incorporated into the perovskite layer and interface layer, with immense potential to further elevate their PCEs to the theoretical peak. Traditional studies focus on the isolated properties of CO, SO and PO molecules but lack a systematic explanation of their common mechanism. In this review, we aim to explore the impact of coordination force-led multifunctional molecules, such as those containing –CO, –SO, –PO and other electron-rich functional groups, on the performance of perovskite films and devices. We provide a comprehensive mechanism analysis of these molecules with different or similar functional groups on modulating the morphology, suppressing the nonradiative recombination, adjusting the energy level alignment and enhancing the operational stability. The application of these coordination force-led multifunctional molecules in (1) the perovskite active layer, (2) bottom and top interface between the perovskite and charge transport layer, and (3) hole and electron transport layers is analyzed in detail. Finally, we provide an outlook on the potential of these molecules for further performance improvement and commercialization of PSCs. We believe that this review holds significant reference value in identifying efficient coordination force-led multifunctional molecules to further improve the performance of PSCs.