Design and Optimization of High-Performance Novel RbPbBr3-Based Solar Cells with Wide-Band-Gap S-Chalcogenide Electron Transport Layers (ETLs)

Inorganic cubic rubidium–lead-halide perovskites have attracted considerable attention owing to their structural, electronic, and unique optical properties. In this study, novel rubidium–lead-bromide (RbPbBr3)-based hybrid perovskite solar cells (HPSCs) with several high-band-gap chalcogenide electron transport layers (ETLs) of In2S3, WS2, and SnS2 were studied by density functional theory (DFT) and using the SCAPS-1D simulator. Initially, the band gap and optical performance were computed using DFT, and these results were utilized for the first time in the SCAPS-1D simulator. Furthermore, the impact of different major influencing parameters, that is, the thickness of the layer, bulk defect density, doping concentration, and defect density of interfaces, including the working temperature, were also investigated and unveiled. Further, a study on an optimized device with the most potential ETL (SnS2) layer was performed systematically. Finally, a comparative study of different reported heterostructures was performed to explore the benchmark of the most recent efficient RbPbBr3-based photovoltaics. The highest power conversion efficiency (PCE) was 29.75% for the SnS2 ETL with Voc of 0.9789 V, Jsc of 34.57863 mA cm–2, and fill factor (FF) of 87.91%, while the PCEs of 21.15 and 24.57% were obtained for In2S3 and WS2 ETLs, respectively. The electron–hole generation, recombination rates, and quantum efficiency (QE) characteristics were also investigated in detail. Thus, the SnS2 ETL shows strong potential for use in RbPbBr3-based hybrid perovskite high-performance photovoltaic devices.