Investigation of highly efficient methyl ammonium lead halide perovskite solar cell with non-textured front surface

High quality methyl ammonium lead iodide (MAPbI₃) perovskite material based single junction solar cell was investigated by simulation. We observed a systematic variation in device performance due to a variation in optical absorption of the active layer. By changing thickness of absorber layer from 50 nm to 1000 nm, we obtained power conversion efficiency (PCE) of the photovoltaic devices varying from 7.9% to 21.1%. Its open circuit voltage (V_oc) varied from 1.26 V to 1.16 V, short circuit current density (J_sc) varied from 7.56 mA/cm² to 22.61 mA/cm² while the fill factor (FF) remained constant at 83% in this variation. Front surface of the solar cell was kept non-textured, however, back reflection of unabsorbed light was used in the analysis. The maximum PCE of 21.1% and J_sc of 22.61 mA/cm² was observed for the solar cell with 1000 nm absorber layer. The J_sc and device efficiency increases with increased thickness of absorber layer (d_i). Therefore, higher PCE can be obtained with a thicker absorber layer. However, we identify that, with 94 nm thick absorber layer, the rate of change of PCE is equal to the rate of change of J_sc, due to the thickness variation. In this cell with 94 nm thick absorber layer (Cell-94), the PCE was 11.5%, nearly half of the PCE obtained with 1000 nm absorber layer. In the Cell-94, the diode ideality factor was 2.04, and reverse saturation current density was 6 × 10⁻¹³ Amp/cm².