High-Efficiency Lead-Free Cs2PdBr6 Perovskite Solar Cells: A SCAPS-1D Numerical Study of Transport Layer Optimization

In this study, a lead-free Cs2PdBr6-based per-ovskite solar cell (PSC) has been numerically simulated systematically with help of SCAPS-1D software with an FTO/ETL/Cs2PdBr6/HTL/Au architecture. Three electron trans-port materials (WO3, TiO2, and SnS2) and three hole transport materials (MoO3, CuI, and GO) were comparatively evaluated across varying layer thicknesses. The optimum thicknesses of the FTO and absorber layers are determines to be 0.01 μm and 5 μm, respectively. Among the investigated transport materials, WO3 and MoO3 used as the electron transport layer (ETL) and the hole transport layer (HTL), respectively, due to their favorable energy band alignment and efficient charge carrier extraction capability. The combined effect of absorber defect density (1010 to 1020 cm−3) and operating temperature (280 K to 360 K) was further analyzed, confirming that crystal quality is the dominant performance-limiting factor. The fully optimized
FTO/WO3/Cs2PdBr6/MoO3/Au device achieves a PCE of 30.62%,Voc = 1.30 V, Jsc = 27.29 mA/cm2, and FF = 86.31% at 300 K, sur-passing all previously reported Cs2PdBr6-based configurations.