The Effect of Deep Defects on the Efficiency Variation of CH3NH3PbI3 Perovskite Solar Cells

Three-dimensional (3D) halide perovskites as CH3NH3PbI3 (3D-MAPI) have shown high performance in the perovskite solar cells. However, deep defects due to lattice disorders in the 3D halide perovskite cause to limit the performance of the halide perovskite solar cells. We have numerically simulated and investigated the optimum deep defect density of the 3D-MAPI layer of the p-i-n solar cell model with the structure of Glass/ITO(TCO)/PEDOT: PSS(HTM)/i-2D-MAPI/i-3D-MAPI/i-2D-MAPI/PCBM(ETM)/Ag. Due to the degradation of the organic components under some environmental conditions, the Pb-based organic perovskite solar cells need protective films. This 2D-3D-2D perovskite solar cell has been modeled as a stable perovskite solar cell, by inserting thin 2D-MAPI layers on both sides of the 3D-MAPI to reduce the degradation and moisture issues. Using SCAPS-1D solar cell simulation software, the deep defect density in the 3D halide perovskite layer was optimized to obtain the best performance of the cell model. Our simulation results have indicated that the deep defect density of the 3D-MAPI layer should not exceed 1012cm−3 for high performance. Also, low dark saturation current density and low Shockley-Read-Hall (SRH) recombination current density were observed at the low deep defect density in the 3D-MAPI layer.