Boosting KSnI₃-based perovskite solar cell efficiency by 22.78% through optimized charge transport and eco-friendly buffer layer

This study presents the development and modeling of lead-free KSnI₃-based perovskite solar cells (PSCs), employing various combinations of charge transport layers and optimizing the device by integrating different buffer layers (IGZO, Cd_0.5Zn_0.5S, and 3C–SiC) using the SCAPS-1D tool. Our focus lies in identifying the most suitable electron transport layer (ETL), hole transport layer (HTL), and low-cost, non-toxic buffer layer to enhance (FTO/ETL/buffer layer/KSnI₃/HTL/Au) device performance. Through meticulous analysis of multiple device parameters, including layer thicknesses, doping concentrations, and defect densities, we have identified SnO₂-ETL, NiO-HTL, and 3C–SiC as the buffer layer, yielding impressive output photovoltaic parameters including power conversion efficiency (PCE of 22.78%), open-circuit voltage (V_OC of 1.3923 V), current density (J_SC of 18.27 mAcm⁻²), and fill factor (FF of 89.57%). These findings underscore the importance of material selection and device optimization in enhancing the efficiency (22.78%) and stability of PSCs, surpassing reported efficiency of up to 20.99%. Our results offer valuable insights into the development of highly efficient KSnI₃-based PSCs, contributing to the progression of renewable energy technologies and sustainable resource utilization.