Comprehensive Analysis of Cesium Silver Bismuth Bromide Perovskite Solar Cells: Enhancing Performance through Optimization and Modeling

Lead‐free perovskite solar cells (PSCs) are attracting increasing attention due to their environmental friendliness and promising performance. This study investigates a double perovskite‐based device using Cs 2 AgBiBr 6 , simulated in SCAPS‐1D (Solar Cell Capacitance Simulator – 1 Dimension). The proposed structure is fluorine‐doped tin oxide (FTO)/SnO 2 /Cs 2 AgBiBr 6 /P3HT/Al. Critical parameters of the absorber layer—thickness, defect density, and electron affinity—along with properties of the electron and hole transport layers (ETL and HTL), such as thickness, doping concentration, and energy alignment, are systematically optimized. Device characteristics including J–V curves (under light and dark), quantum efficiency, generation rate, carrier concentration, temperature effects, band diagrams, and back contact work function are analyzed. The optimized configuration achieves a power conversion efficiency (PCE) of 17.56%, with an open‐circuit voltage (Voc) of 1.79 V, a short‐circuit current density (Jsc) of 13.26 mA/cm 2 , and a fill factor (FF) of 75.41%. These results demonstrate the promising potential of Cs 2 AgBiBr 6 as a stable and efficient absorber for lead‐free PSCs, aligning well with recent experimental findings. This work provides a valuable foundation for further development of environmentally friendly, tin‐halide‐based photovoltaic technologies.