Investigation of 2T Pb-free wide bandgap perovskite/c-Si tandem device through simulation by SCAPS-1D

Shockley Queisser's theory states that the efficiency of single-junction solar cells is restricted. This constraint can be avoided by employing a tandem (stacking multiple cells) setup. Furthermore, stacking layers such as Perovskite/silicon in tandem architecture might boost efficiency. In this research, SCAPD-1D was used to simulate a monolithic 2T Perovskite/silicon tandem solar cell. The tandem configuration is composed of a narrow bandgap (1.1 eV) crystalline silicon Heterojunction with an intrinsic thin layer (HIT) solar cell at the bottom and a wide bandgap (1.8 eV) lead-free Perovskite (Cs2AgBi0.75Sb0.25Br6) solar cell on top. The proposed tandem device is simulated as a standalone and integrated structure. The PCE of the calibrated standalone cell is 14.54% (top cell) and 21.66% (bottom cell), respectively. The calibrated cells are used to design an integrated tandem configuration. The current matching condition is accomplished at varied thicknesses of top and bottom absorber layers. A bottom cell's ideal current matching thickness is 230 mu m, while a perovskite top cell is 550 nm. The overall conversion efficiency of the tandem device is 26%, with an FF of 79.18%.