Numerical analysis and device modelling of a lead-free SrPI/SrSbI double absorber solar cell for enhanced efficiency.

Halide perovskites are the most promising options for extremely efficient solar absorbers in the field of photovoltaic (PV) technology because of their remarkable optical qualities, increased efficiency, lightweight design, and affordability. This work examines the analysis of a dual-absorber solar device that uses SrSbI as the bottom absorber layer and SrPI as the top absorber layer of an inorganic perovskite through the SCAPS-1D platform. The device architecture includes ZnSe as the electron transport layer (ETL), while the active layer consists of SrPI and SrSbI with precise bandgap values. The bandgap value of SrSbI is 1.307 eV and SrPI is 1.258 eV. By employing double-graded materials of SrPI/SrSbI, the study achieves an optimized efficiency of up to 34.13% with a of 1.09 V, FF of 87.29%, and of 35.61 mA cm. The simulation explores the influence of absorber layer thickness, doping level, and defect density on electrical properties like efficiency, short-circuit current, open-circuit voltage, and fill factor. It also examines variations in temperature and assesses series and shunt resistances in addition to electrical factors. The simulation's output offers valuable insights and suggestions for designing and developing double-absorber solar cells.