Enhancing the efficiency of lead-free Cs2BiAgBr6 double perovskite solar cells

In the present research, the photovoltaic performance of a lead-free double perovskite photovoltaic cell using Cs2AgBiBr6 as the active layer was systematically investigated through numerical simulation using OghmaNano software. The device structure considered was FTO/TiO2/Cs2AgBiBr6/Spiro-OMeTAD/Au. The study focused on optimizing the physical and electrical parameters, including the thickness of each layer, doping concentration, and series resistance, to enhance device efficiency. The optimal device performance was achieved when the active layer thickness was set to 500 nm, combined with well-tuned transport layers and favorable electrical conditions. Under illumination conditions of AM1.5G (1000 W/m²) at 300 K, the optimized device achieved a short-circuit current density (Jsc) of 7.97 mA/cm², an open-circuit voltage (Voc) of 0.988 Volts, a fill factor (FF) of 86.52%, and a power conversion efficiency (PCE) of 6.81%. The findings suggest the promise of Cs2AgBiBr6 as a sustainable and environmentally friendly substitute for perovskites containing lead. Nonetheless, the limited of light absorption in the near-infrared (NIR) spectrum suggests a need for advanced light management strategies. Future developments may include the integration of tandem architectures to further improve spectral utilization and device efficiency