Improving the Efficiency of a New Perovskite Solar Cell Based on Sr3SbI3 by Optimizing the Hole Transport Layer

Strontium antimony iodide (Sr 3 SbI 3 ) showing distinct structural, electrical, and optical features is a recently developing potential absorber material for designing efficient and affordable solar cells. In this study, the physical properties such as structural, optical, and electronic properties including the photovoltaic (PV) performance of Sr 3 SbI 3 absorber-based double-heterojunction solar cells have been studied and analyzed systematically. At first, the optoelectronic properties of the Sr 3 SbI 3 absorber layer were investigated using first-principles density functional theory in detail. In the beginning, the impact of several probable metals as rear and front contacts was considered to identify the metal–semiconductor interface’s least resistive junction, where aluminum (Al) was mentioned as the best possible front contact and nickel (Ni) as the back contact. Then, the PV performance of novel Sr 3 SbI 3 absorber-based cell structures for the different hole transport layers (HTLs) of MoO 3, Cu 2 O, P3HT, CuO, and CFTS, with SnS 2 as the transition-metal dichalcogenide electron transport layer (ETL), was studied at different layer thicknesses, doping density, total and interface defect densities, working temperature including the rate of carrier generation and recombination by determining the quantum efficiency, and the current density–voltage ( J – V ) via SCAPS-1D simulator software. Finally, optimization of all HTLs with the absorber, the highest power conversion efficiency (PCE) of 33.25% with J SC of 34.72 mA/cm 2, FF of 85.92%, and V OC of 1.11 V, was obtained for MoO 3 HTL, while the minimum PCE of 17.12%, with J SC of 29.57 mA/cm 2, FF of 80.61%, and V OC of 0.72 V, was obtained for CFTS HTL, respectively. These results unveil the strong potentiality of the Sr 3 SbI 3 absorber, with SnS 2 as ETL and MoO 3 as HTL for experimental fabrication of the high-performance perovskite heterostructure solar cell in the near future.