Boosting efficiency above 30 % of novel inorganic Ba3SbI3 perovskite solar cells with potential ZnS electron transport layer (ETL)

The inorganic Ba3SbI3 perovskite has emerged as a promising, stable absorber material for efficient and cost-effective solar cells, owing to its intriguing compositional, structural, electrical, and optical properties. This study delves into the potential of Iodide-based Ba3SbI3 perovskites, known for their relative stability, as ab-sorbers in conjunction with a ZnS electron transport layer (ETL) to create a high-performance solar cell heter-ostructure. Using the SCAPS-1D simulator, we first estimate the absorption spectrum and bandgap of the Ba3SbI3 absorber layer through density functional theory (DFT). This obtained spectrum serves as a crucial input for device simulation. We further optimize the work function of the rear electrode to enhance the photovoltaic (PV) performance of the ZnS/Ba3SbI3 heterostructure solar cell. Various parameters including doping density, absorber thickness, and bulk/interface defect density are carefully considered. Additionally, we investigated generation and recombination rates, current density-voltage (J-V) characteristics, and corresponding quantum efficiency (QE). Under optimized conditions, our study achieves a remarkable maximum power conversion ef-ficiency (PCE) of 30.49 %, accompanied by a photocurrent density (JSC) of 54.63 mA/cm2, fill factor (FF) of 83.75 %, and open circuit voltage (VOC) of 0.67 V in the ITO/ZnS/Ba3SbI3/Ni structure. This comprehensive analysis offers valuable insights and methodologies for the experimental design of high-performance and stable photovoltaic devices based on Ba3SbI3 perovskite.