Abstract
KSnI(3)-based perovskite solar cells have attracted a lot of research interest due their unique electronic, optical, and thermal properties. In this study, we optimized the performance of various lead-free perovskite solar cell structures-specifically, FTO/Al-ZnO/KSnI(3)/rGO/Se, FTO/LiTiO(2)/KSnI(3)/rGO/Se, FTO/ZnO/KSnI(3)/rGO/Se, and FTO/SnO(2)/KSnI(3)/rGO/Se, using the SCAPS-1D simulation tool. The optimization focused on the thicknesses and dopant densities of the rGO, KSnI(3), Al-ZnO, LiTiO(2), ZnO, and SnO(2) layers, the thickness of the FTO electrode, as well as the defect density of KSnI(3). This yielded PCE values of 27.60%, 24.94%, 27.62%, and 30.21% for the FTO/Al-ZnO/KSnI(3)/rGO/Se, FTO/LiTiO(2)/KSnI(3)/rGO/Se, FTO/ZnO/KSnI(3)/rGO/Se, and FTO/SnO(2)/KSnI(3)/rGO/Se perovskite solar cell configurations, respectively. The FTO/SnO(2)/KSnI(3)/rGO/Se device is 7.43% more efficient than the FTO/SnO(2)/3C-SiC/KSnI(3)/NiO/C device, which is currently the highest performing KSnI(3)-based perovskite solar cell in the literature. Thus, our FTO/SnO(2)/KSnI(3)/rGO/Se perovskite solar cell structure is now, by far, the most efficient PSC design. Its best performance is achieved under ideal conditions of a series resistance of 0.5 Ω cm(2), a shunt resistance of 10(7) Ω cm(2), and a temperature of 371 K.