The growing interest in high-efficiency solar energy technologies has driven research on multijunction solar cells to flourish over the last several years. This study sheds light on the optical, structural, and morphological aspects of the (CH3NH3)3Bi2I9 ((MA)3Bi2I9) film by fabricating and analyzing it experimentally. This thorough investigation lays the groundwork for more research into the film's possible uses in solar cell technology. We performed simulations to enhance the efficiency of two-terminal (2T) perovskite/perovskite double junction and perovskite/perovskite/c-Si triple-junction solar cells (TJSC) by using the MA3Bi2I9 material. The power conversion efficiency was greatly increased by using 2T triple-junction solar cells; the increase was around 116.59% from single junction (13.80-29.89%) and 31.91% from double junction (22.66-29.89%). As far as we know, this is the first investigation of the efficacy of MA3Bi2I9 as a top layer in multijunction tandem configurations. This revolutionary approach allows both academics and industry experts to produce cost-effective and efficient tandem solar cells, thereby enhancing earth-based solar energy development.
Keywords: (MA)3Bi2I9; HTLs; defect analysis; double junction; experimental and simulation; triple junction; two-terminal.