Design and simulation of the potential of lead-free Ag₃Bi_1.1I_6.3 perovskite solar cells with different charge transport for energy enhancement

Emerging perovskite solar cells (PSCs) are facing environmental toxicity issues due to lead-based perovskites, and long-term stability remains a challenge. In recent years, silver bismuth iodides (Ag₃Bi_1.1I_6.3) have gained attention as an absorber due to their lead-free, non-toxic, and cost-effective characteristics. However, device performance is still low so research is necessary to make it marketable. In this study, SCAPS-1D simulation is utilized to develop PSCs with an Ag₃Bi_1.1I_6.3 absorber, C₆TBTAPH₂ Hole transport layer (HTL), and four distinct electron transport layers (ETLs) (STO, MZO, ZnSe, PC₆₀BM) under standard illumination. In light of these factors, a thorough investigation of the FTO/ETL/Ag₃Bi_1.1I_6.3/C₆TBTAPH₂/Au combination was conducted to evaluate the influence of power conversion efficiency (PCE). For each of the four assessed combinations, modifications were made to the absorber, the HTL, the ETL thickness, the acceptor density of the HTL, the acceptor doping, and the defect density of the absorber. The effects of these topologies on quantum efficiency, <i>J</i>-<i>V</i> characteristics, generation and recombination processes, series and shunt resistance, and temperature impact were also investigated. In the end, the most effective cell in this investigation was the FTO/MZO/Ag₃Bi_1.1I_6.3/C₆TBTAPH₂/Au configuration with a PCE of 20.72%, <i>V</i> _OC of, <i>J</i> _SC of, and FF of at 300 K temperature. The previously described results have the potential to significantly advance the development of lead-free PSCs, which are more environmentally friendly and efficient, thereby opening the door for their eventual widespread use.