The efficiency of perovskite-based solar cells (PSCs) with single and double absorber layers has been examined in this work. First, we simulated and examined the performance of 2 single-junction perovskite solar cells based on CsPbI 3 and CsSnI 3 . After that, we adjusted the performance of the bilayer solar cell by simulating a PSC using CsPbI 3 and CsSnI 3 as the 2 absorber layers. All simulations were performed using the SCAPS-1D program under standard AM1.5 G solar illumination to reflect real-world operating conditions. The SCAPS-1D simulation program is used to numerically optimize a dual-absorber PSC structure Indium Tin Oxide (ITO/SnO₂/CsSnI₃/CsPbI₃/Spiro-OMeTAD/Au), with an emphasis on the impacts of operating temperature, absorber layer thickness, and defect density. Optimal power conversion efficiency (PCE) of 31.45% was achieved at 0.2μm (200 nm) of the CsSnI 3 absorber layer by increasing the thickness from 0.2 to 0.7μm, which enhanced short-circuit current density (Jsc) but significantly decreased open-circuit voltage (Voc) and fill factor (FF). Changing the thickness of CsPbI₃ from 0.5 μm to 1 μm revealed comparable patterns, with PCE reaching 31.45% and Jsc rising at 1 μm. Defect density variations at the Spiro-OMeTAD/CsPbI₃ interface and in CsSnI₃ exhibited no effect, while high bulk defect density in CsPbI₃ led to a dramatic PCE drop from 31.45% to 2.99%. According to temperature analysis, Jsc increases as temperature increases, but due to thermal losses, Voc, FF, and PCE decrease from 300 K to 400 K. These findings emphasize that for high-performance PSCs, absorber thickness optimization, defect density minimization, and temperature effects consideration are necessary. • Optimal absorber thickness: 200 nm CsSnI₃ and 1 μm CsPbI₃, achieving PCE = 31.45%. • Bulk defects in CsPbI₃ and interface defects (Spiro-OMeTAD/CsPbI₃ and CsPbI₃/CsSnI₃) significantly reduce efficiency. • Performance declines with increased temperature; lower operating temperatures improve stability. • Minimal impact of HTL (Spiro-OMeTAD) and ETL (SnO 2 ) thickness variations on overall efficiency. • CsSnI₃ primarily aids charge transport; defects in CsSnI₃ have negligible effect.
khatun et al. (Tue,) studied this question.