Device-level optimization and admittance-impedance analysis of quasi-2D perovskite solar cells

Abstract Perovskite solar cells (PSCs) have recently gained attention due to their high -power conversion efficiency, low fabrication cost and the increasing global demand for sustainable energy sources. However, the long-term stability of PSCs remains a major challenge. In this context, two-dimensional(2D) perovskites can be seen as a viable solution due to their high stability. This work focuses on quasi-2D PSC architecture which offers a balance between high efficiency and enhanced stability. The absorber material used in this study is (MAMP)MA n −1 Pb n I 3n+1 , an MAMP spacer-based Dion-Jacobson (DJ) 2D perovskite. Solar Cell Capacitance Simulator (SCAPS) is used to simulate and optimize the performance of the device. After the device is calibrated, it is optimized systematically. Suitable Electron Transport Layer (ETL) and Hole Transport Layer (HTL) materials, along with their optimum thicknesses, are selected as C 60 (10 nm) and CBTS (200 nm) respectively. Subsequently, absorber layer thickness along with its defect density and doping density are optimized. The absorber layer thickness is set to 1.5 μm. The defect density is set to 1 × 10 14 cm − 3 and the absorber doping density is set to 1 × 10 16 cm − 3 . The optimized cell achieved a simulated J SC of 21.36 mA cm − 2 , V OC of 1.238 V, FF of 77.96%, and PCE of 20.60%. Further, the effects of series resistance and operating temperature on the device are analyzed. Finally, Admittance and Impedance analysis is performed to gain deeper insight into the charge transport, defect states and opto-electronic behavior of this device. These results demonstrate that systematic optimization of device parameters is an effective approach for improving the performance of quasi-2D PSCs.