Exploring the impact of strain on the electronic and optical properties of inorganic novel cubic perovskite Sr3PI3

Abstract

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 JSC of 34.65 mA cm−2, FF of 87.30%, and VOC 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.