Unlocking durability and efficiency in perovskite solar cells via sulfur -based thiazoline engineered passivation

Thiol-, thione-, and thiazoline-derived molecules have attracted considerable attention as additives and ligands for enhancing both the efficiency and stability of perovskite solar cells (PSCs). In this study, we explore the use of a thiazoline-based compound, 2-mercaptothiazoline (2MT, C₃H₅NS₂), to address halide vacancies in the mixed perovskite composition (FAPbI₃)₀.₉₅(MAPbBr₃)₀.₀₅, a widely utilized formulation in high-performance PSCs. Introducing 2MT during the antisolvent step was found to promote favorable film formation, suppressing the non-photoactive δ-phase while reducing residual PbI₂. The presence of this ligand also encouraged improved crystal growth, resulting in larger grains that support better device performance. The treated films exhibited enhanced charge carrier dynamics, extended lifetimes, and more efficient charge extraction, resulting in devices with a higher power conversion efficiency (22.6% compared to 19.97% for the control). In addition, the devices demonstrated improved operational and environmental stability. Overall, these results suggest that sulfur-containing additives play a particularly effective role in perovskite passivation, owing to their strong interaction with Pb²⁺ centers and their ability to compensate for the labile halide sites (Wang et al., Energy Environ Sci 17:1368–1386, 2024).