Performance improvement of lead-free CsSnCl3-based perovskite solar cell using multiple ETLs: A SCAPS-1D simulation study

Cesium tin chloride (CsSnCl3) is a potential and ecologically safe material for lead-free perovskite solar cells (PSCs). CsSnCl3 is a strong candidate for sustainable energy applications due to its affordability, high energy efficiency, and excellent thermal stability. We simulated various CsSnCl3 device structures with different electron transport layers (ETLs)—viz. WS2, C60, and ZnSe—in combination with CBTS as the hole-transport layer (HTL), using the one-dimensional solar cell capacitance simulator (SCAPS-1D). We quantitatively evaluated the influence of the absorber layer thickness, doping concentration, defect density, and characteristics of the ETL and HTL on relevant photovoltaic (PV) parameters, such as power conversion efficiency (PCE) (η), short-circuit current density (JSC), open-circuit voltage (VOC), and fill factor (FF). The findings revealed that the choice of ETL has a great impact on the performance of the device. WS2, C60, and ZnSe led to the highest PCEs at 22.09%, 19.94%, and 21.80%. Then, the effect of other factors was investigated, including capacitance-voltage behavior, interface defect, Mott–Schottky behavior, current density-voltage (J-V), quantum efficiency (QE), and recombination rates. The results were compared with the earlier research conducted on CsSnCl3-based PSCs to assess enhancements and long-term sustainability. To summarize, this paper proposes the most effective and high-performance device configurations in lead-free CsSnCl3-based PSCs, as part of developing sustainable and cost-effective PV technologies.