▎ 摘　　要

Lead-free perovskite solar cells (PSCs) have sparked considerable interest in the optoelectronics research community and gained recognition in recent years due to their practical use in solar energy. The primary obstacles in producing PSCs are stability and toxicity due to the immersion of organic-cation and lead in perovskite material. This study presents an electrical simulation of a caesium-indium-based lead-free hybrid PSC using SCAPS-1D software. Spiro-MeOTAD is a typical hole transport material (HTM) used in PSC, although it has not always been suggested because of its high design cost and stability constraints. This study aims to evaluate the performance of lead-free double perovskite material as an absorber layer along with different hole transport materials (HTM). We discovered that the lead-free double perovskite combined with graphene-oxide (GO) and reduced graphene oxide (rGO) produces the best results. Furthermore, the light-harvesting layer and HTM layer has optimized via thickness, defects, doping concentration, and temperature. The improved PSC structure achieves power conversion efficiency (PCE) of more than 24%, and the results of the optimized PSC have compared to the results of the experimentally implemented PSC. This work also used C-V measurements on the optimized structure to determine the device contact potential and doping concentration. The optimized results suggest a feasible future route for creating lead-free PSC with high productivity and free from stability or toxicity issues.