Design and Simulation of Lead-free Flexible Perovskite Solar cell Using SCAPS-1D.

Abstract

Despite perovskite solar cells’ rapidly increasing efficiency, industrializing and commercializing the device presents several challenges. Top among these is toxicity due to the material’s lead-based perovskite usage, which causes rapid degradation. Because of this challenge, researchers have recently become interested in lead-free perovskite materials. In this research, we investigate using the SCAPS simulation software to optimize a lead-free flexible solar cell. Lead (Pb), which belongs to group 14, can likely be replaced with bismuth (Bi), which belongs to group 15. In this study, the structure of the device is an n-i-p planar lead-free heterostructure flexible perovskite solar cell (FPSC) comprised of a Polyethylene Terephthalate/Indium Tin Oxide (PET/ITO) substrate; [6,6]-phenyl C61 butyric acid methyl ester (PCBM) Electron Transport Layer (ETL); methyl ammonium bismuth iodide (CH3NH3BiI3) as an absorber; Spiro-OMeTAD as a Hole Transport Layer (HTL); and silver (Ag) as the electrode. We optimised cell performance and efficiency with an absorber layer of 100 nm and an optimised temperature of 300 K. This absorber layer’s thickness and defect density were considered. The defect density of the FPSC is indirectly proportional to the device’s absorption coefficient (alpha). We obtained a power conversion efficiency (PCE) of 18.80%, a current density (JSC) of 35.59 mA/cm2, an open circuit voltage (VOC) of 0.633 V, and a fill factor (FF) of 83.43%. We also observed that the FF is inversely proportional to the thickness of the absorber layer of the FPSC.