Ambient-Synthesized Tin-Based Single and Double Perovskite Additives for High-Efficiency and Long-Term-Stable Dye-Sensitized Solar Cells

Abstract

This study presents novel tin-based perovskites as multifunctional additives for liquid electrolytes in dye-sensitized solar cells (DSSCs), enabling significant improvements in photovoltaic performance and operational stability. Single- and double-cation tin-based perovskites (Pe and Ca-Pe) were synthesized under ambient conditions using the ligand-assisted reprecipitation method and subsequently incorporated into conventional liquid electrolytes. These perovskite additives effectively address traditional DSSC challenges, including limited long-term stability and suboptimal charge transport. Electrochemical characterization revealed that incorporating Pe and Ca-Pe significantly enhances ionic conductivity and reduces charge-transfer resistance at the electrode–electrolyte interface, resulting in improved charge-transport kinetics. Under standard AM 1.5G illumination, DSSCs employing LE + Pe achieved a power conversion efficiency (PCE) of 9.55%, while LE + Ca-Pe devices delivered a superior PCE of 10.99% and a short-circuit current density of 19.38 mA cm⁻². Long-term stability testing at 23 °C demonstrated excellent durability, with LE + Ca-Pe-based devices retaining 96.6% of their initial efficiency after 720 h of continuous operation. The benefits extended to indoor illumination (6097 Lx), where LE + Pe and LE + Ca-Pe devices achieved PCEs of 25.45% and 26.09%, respectively, surpassing baseline devices. These results demonstrate that tin-based perovskite additives offer a promising pathway toward high-performance DSSCs for both outdoor and indoor energy-harvesting applications.