In recent years, inorganic perovskite materials have attracted a lot of attention in the field of solar technology due to their exceptional structural, optical, and electronic properties. This study thoroughly investigated, using first-principles density-functional theory (FP-DFT), the impact of compressive and tensile strain on the structural, optical, and electrical properties of the inorganic cubic perovskite Sr₃AsI₃. The unstrained planar Sr₃AsI₃ molecule exhibits a direct bandgap of 1.265 eV value at Γ point. The bandgap of the Sr₃AsI₃ perovskite is lowered to 1.212 eV when the relativistic spin-orbital coupling (SOC) effect is subjected in the observations. In addition, the structure's bandgap exhibits a falling prevalence due to compressive strain and a slight rise due to tensile strain. The optical indicators such as dielectric functions, absorption coefficient, reflectivity, and electron loss function show that this component has a great ability to absorb in the visible range in accordance with band characteristics. When compressive strain is raised, it is discovered that the spikes of the dielectric constant of Sr₃AsI₃ move to lower photon energy (redshift), and conversely, while growing tensile strain, it exhibits increased photon energy changing behavior (blueshift). As a result, the Sr₃AsI₃ perovskite is regarded as being ideal for use in solar cells for the production of electricity and light management.

Strontium antimony iodide (Sr₃SbI₃) is one of the emerging absorbers materials owing to its intriguing structural, electronic, and optical properties for efficient and cost-effective solar cell applications.

Inorganic perovskite materials have drawn great attention in the realm of solar technology because of their remarkable structural, electronic, and optical properties. Herein, we investigated strain-modulated electronic and optical properties of Sr₃PI₃, utilizing first-principles density-functional theory (FP-DFT) in detail. The SOC effect has been included in the computation to provide an accurate estimation of the band structure. At its Г(gamma)-point, the planar Sr₃PI₃ molecule exhibits a direct bandgap of 1.258 eV (PBE). The application of the spin-orbit coupling (SOC) relativistic effect causes the bandgap of Sr₃PI₃ to decrease to 1.242 eV. Under compressive strain, the bandgap of the structure tends to decrease, whereas, under tensile strain, it tends to increase. Due to its band properties, this material exhibits strong absorption capabilities in the visible area, as evidenced by optical parameters including dielectric function, absorption coefficient, and electron loss function. The increase in compressive or tensile strain also causes a red-shift or blue-shift behavior in the photon energy spectrum of the dielectric function and absorption coefficient. Finally, the photovoltaic (PV) performance of novel Sr₃PI₃ absorber-based cell structures with SnS₂ as an Electron Transport Layer (ETL) was systematically investigated at varying layer thicknesses using the SCAPS-1D simulator. The maximum power conversion efficiency (PCE) of 28.15% with J_SC of 34.65 mA cm⁻², FF of 87.30%, and V_OC of 0.92 V was found for the proposed structure. Therefore, the strain-dependent electronic and optical properties of Sr₃PI₃ studied here would facilitate its future use in the design of photovoltaic cells and optoelectronics.