Photovoltaic cell parameter analysis of CsPb_1−xZn_xIBr₂-based all-inorganic perovskite solar cells for low-temperature processed flexible devices

All-inorganic CsPbIBr₂ absorber-based perovskite solar cells (PSCs) offer decent stability under a moist atmosphere. However, the processing temperature is ∼ 200 ℃, which cannot be adopted for the flexible PSCs. Thus, a low-temperature processed Zn-substituted CsPbIBr₂ (CsPb_1−xZn_xIBr₂) is used. In this study, two structures (FTO/SnO₂/CsPb_1−xZn_xIBr₂/MoO₃/Au (cell #1) and FTO/ZnO/CsPb_1−xZn_xIBr₂/NiO/Au (cell #2)) of the PSC are used to investigate the potential of CsPb_1−xZn_xIBr₂ absorber via numerical simulation. The results revealed that for the well-passivated CsPbIBr₂ absorber layer, cell #2 offers a better open circuit voltage than cell #1. At a low defect level, the efficiency of cell #2 is higher than the efficiency of cell #1. But at a high defect level, both cells offer similar power conversion efficiency (η). PV cell parameter analysis revealed that cell #1 delivers a greater photogenerated current than that of cell #2. The shunt resistance obtained for cell #1 and cell #2 is 4.25 × 10⁵ and 1.48 × 10⁷ Ωcm², respectively. R_s values obtained for cell #1 and cell #2 are 16.40 and 11.66 Ωcm², respectively. The recombination in cell #1 is much lower than that in cell #2. The results revealed that a maximum η of 16.07 and 17.11% can be achieved for cell #1 and cell #2, respectively.