Study of defects in CH3NH3PbI3-based perovskite solar cells

Abstract

The present work will focus on the investigation of the influence of defects density and carriers capture cross-section are in absorption layer on the performance of perovskite solar cells. Furthermore, the impact of defect density in the electron transport material ETM/absorber interface layer will also be studied. The hybrid halide perovskite solar cells are chosen in this work and will be simulated by using one-dimension solar cells capacitance simulation SCAPS-1D. The proposed structure of the perovskite solar cell is a planar FTO/ETM/perovskite/HTM based on TiO2 and Spiro-OMeTAD as electron transport layer ETM and hole transport layer HTM, respectively, and on CH 3NH 3PbI 3 as absorber layer (perovskite). The results showed that when the defect density in the absorber layer was varied from 10 10cm -3 to 10 18 cm -3, the cell parameters, open circuit voltage (V oc), the short circuit current (J sc ), the fill factor (FF), and the efficiency (PCE)were significantly decreased. At high defect density (10 18 cm -3), the defect affects negatively on the cell performance due to the high recombination rate of Shockley Read Hall. Similarly, the capture cross section exhibits similar behaviour in the active layer. By increasing the defect density in the ETM/absorber interface layer, the main cell parameters PCE, FF, and J sc are slightly reduced and there has been no noticeable impact on V oc .