Advanced Simulation and Performance Optimization of Eco‐Friendly Bilayer Perovskite Solar Cell Using SCAPS‐1D

ABSTRACT In this work a comprehensive simulation is conducted to develop, design and enhance the efficiency of a bilayer Perovskite Solar Cell (PSC) through SCAPS‐1D. In this work, the efficiency of bilayer PSC is optimized for two non‐toxic, efficient, ecofriendly, and stable absorber materials (i) calcium zirconium sulfide (CaZrS 3 ), a chalcogenide material and (ii) formamidinium tin iodide (FASnI 3 ), a tin‐based material. Initially the optimization is conducted for single layer PSCs with configurations FTO/TiO 2 /CaZrS 3 /Spiro‐OMeTAD and FTO/TiO 2 /FASnI 3 /Spiro‐OMeTAD are first analyzed separately using SCAPS‐1D software. Subsequently, the two absorber layers CaZrS 3 and FASnI 3 are integrated to design a bilayer structure which is further optimized. The outcomes of the final optimization show that the proposed bilayer PSC attains a power conversion efficiency (PCE) 23.00% and a fill factor (FF) 86.00%, thereby exceeding the photovoltaic (PV) performance of both individual single‐junction perovskite solar cells as well as the unoptimized bilayer structure. The optimized device further demonstrates superior charge transport behavior, reduced recombination losses, and better overall photovoltaic performance, which are attributed to the synergistic interaction between the two absorber layers incorporated in the bilayer architecture. This study highlights the significance of incorporating bilayer structures and strategic material selection for ETL, HTL and front contact in advancing perovskite solar cell technology.