Efficiency optimization of a solar cell structure containing a two-dimensional BA2PbI4 perovskite layer

Power conversion efficiency of perovskite solar cells has increased rapidly in recent years. This progress has been made possible through the optimization of the device architecture, the improvement of hole and electron transport layers, and production of high-quality perovskite films. However, 3D perovskite solar cells exhibit low stability to moisture, heat, and light. To address this stability issue, 2D perovskite layers can be incorporated into the structure. In this study, an FTO/ETL/3D perovskite/2D perovskite/HTL/Au solar cell in a NIP configuration was modeled. The proposed structure was simulated using SCAPS-1D software under AM1.5G solar spectrum illumination (1000 W/m²) and at an ambient temperature of 300 K. According to the comparative analysis of different HTL and ETL materials, NiO and SnO2 were chosen as the most suitable HTL and ETL materials, respectively. As the thickness of the 3D perovskite layer increased, the Voc and FF values decreased while the Jsc value increased. Conversely, increasing the thickness of the 2D perovskite layer negatively affected the solar cell performance according to the simulation results. Additionally, an increase in defect density within the 3D perovskite layer was found to degrade the solar cell performance. It was aimed to design an optimal solar cell to minimize the stability problems of perovskite solar cells with the simulations. A NIP solar cell structure with FTO/SnO2/3D perovskite/2D perovskite/NiO/Au configuration, featuring a 900 nm thick 3D perovskite layer and a 9 nm thick 2D perovskite capping layer, was designed. The optimal solar cell simulation resulted in a Voc of 1,40 V, a Jsc of 25,59 mA/cm², a FF of 79,59%, and a PCE of 28,58%.