Through optimization, the thickness of each layer was fine-tuned to enhance performance. The V2O5 HTM showed optimal performance at a thickness of 0.035 µm, while the CsSnI3 absorber layer achieved maximum efficiency at 0.275 µm. The WS2 ETM exhibited optimal performance at 0.015 µm, balancing electron transport and minimizing resistance. Adjusting the doping density further enhanced device performance, with higher doping in the V2O5 HTM (1×10 19 1/cm³) improving hole mobility and lower doping in the CsSnI3 absorber (1×10 16 1/cm³) minimizing recombination. Similarly, higher doping in the WS2 ETM (1×10 19 1/cm³) optimized electron transport. Lower defect density in the CsSnI3 absorber (1×10 14 1/cm³) also proved crucial, as it extended carrier lifetime and diffusion length, reducing recombination and further boosting efficiency.