Modeling the Impact of Back Contact Variation on CH₃NH₃SnI₃ - Based Perovskite Solar Cells Using SCAPS-1D

Abstract:

Perovskite solar cells (PSCs) have emerged as promising candidates in the field of photovoltaics due to their high efficiency and low-cost fabrication potential. However, most high-performance PSCs are based on lead-containing materials, raising significant environmental and health concerns that hinder their commercialization. To overcome this limitation, researchers are actively exploring eco-friendly, lead-free alternatives. In this study, a lead-free perovskite solar cell using CH₃NH₃SnI₃ as the absorber layer is proposed. The device structure includes fluorine-doped tin oxide (FTO) as the transparent conducting oxide, ZnO nanorods (ZnO:NR) as the electron transport layer (ETL), and Spiro-OMeTAD as the hole transport layer (HTL). The SCAPS-1D simulation tool is employed to analyze and optimize the performance of the device. Key parameters such as absorber layer thickness, doping concentration, defect density, and the thicknesses of the ETL and HTL were systematically varied to identify optimal conditions. The simulation results reveal that under optimized conditions, the device achieves a power conversion efficiency (PCE) of 18.49 %, with an open-circuit voltage (VOC) of 0.9248 V, a short-circuit current density (Jsc) of 29.57 mA/cm², and a fill factor (FF) of 67.61 %. These findings support the potential of lead-free PSCs for sustainable solar energy applications.

 Keywords: Perovskite Solar Cell, SCAPS-1D, CH3NH3SnI3, HTL, ETL, Absorbed Layer