Enhancing the efficiency of methylammonium silicon iodide-based perovskite solar cells: Optimization of charge transport layers and device parameters

• Lead-free Si based MASiI 3 PSCs simulated using SCAPS-1D. • Optimized the best TiO 2 (ETL) and Cu 2 O (HTL). • Optimized the effect of thickness, doping density, defect density on the absorber layer. • Studied impact of the interface density, back electrodes, shunt and series resistance. • Optimized the maximum PCE of 29.78 % in Si based perovskite cells. Methylammonium Silicon Iodide (MASiI 3 ), has attracted considerable interest due to its potential to improve the stability of the devices. However, MASiI 3 -based perovskite solar cells (PSCs) have yet to reach the maximum limit at the theoretical level. In this work, SCAPS-1D device modeling to improve the efficiency of Si-based PSCs, with a focus on key critical parameters. In the optimization process included the selection and tuning of the electron transport layer (ETL) and hole transport layer (HTL), optimization of peroveskiter layer thickness, accepter and donor doping concentration as well as defect density, resistance (shunt and series), back electrode materials, and the impact of envirment temperature. Through a comparative analysis of multiple materials, TiO 2 emerged as the most suitable ETL and Cu 2 O as the optimal HTL, owing to their favorable band-alignment. The chosen HTL and ETL materials exhibited excellent charge carrier transport properties, and optimization of the absorber layer parameters contributing to improved cell efficiency. The improved cell attained a V oc of 0.898 V, J sc of 42.48 mA/cm², FF of 78.2 %, and a notable ɳ of 29.78 %. These findings demonstrated that the potential Si based perovskite cell structure with using TiO 2 and Cu 2 O as charge transport layers and provide a solid foundation for further improvements in perovskite cell technology.