Exploring the Impact of Various Organic and Inorganic Electron Transport Layers in Highly Stable FA_0.75MA_0.25Sn_0.95Ge_0.05I₃- Based Perovskite Solar Cells

Perovskite solar cells (PSCs) have garnered significant attention owing to their elevated efficiency, with <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{FA}_{0.75}\mathbf{MA}_{0.25}\mathbf{Sn}_{0.95}\mathbf{Ge}_{0.05}\mathbf{I}_{3}$</tex> identified as a notable absorber material because of their high stability and cost-effectiveness. This research investigates the efficacy of the hybrid material as an absorber layer in conjunction with NiO as the hole transport layer (HTL) and several organic-inorganic electron transport layers (ETLs), namely <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{WS}_{2}$</tex>, PC <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${}_{60}\mathbf{BM}$</tex>, PFN <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$:\mathbf{Br}$</tex>, and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{ZnTe}$</tex>. The research employs SCAPS-1D numerical simulations to optimize key parameters, including the band diagram, thickness, and doping concentration of the absorber layer and ETL, to improve photovoltaic performance. The analysis demonstrates significant variations in power conversion efficiency (PCE) among configurations, contingent upon the selection of ETL. The <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Glass}/\mathbf{FTO}/\mathbf{WS}_{2}/\mathbf{FA}_{0.75}\mathbf{MA}_{0.25}\mathbf{Sn}_{0.95}\mathbf{Ge}_{0.05}\mathbf{I}_{3}/\mathbf{NiO}/\mathbf{Au}$</tex> structure demonstrated optimal performance, with an open-circuit voltage <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{V}_{\text{OC}})$</tex> of 1.12 V, a PCE of 31.01%, a fill factor (FF) of 88.21%, and a short-circuit current density <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathbf{J}_{\text{SC}})$</tex> of 31.12 m.A/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>. Devices utilizing ETLs like PC <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${}_{60}\mathbf{BM}$</tex>, PFN:Br, and ZnT <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$e$</tex> achieved PCEs of 29.37%, 26.89%, and 29.70%, respectively. Furthermore, for all PSC structures, the associated current density-voltage (J-V) characteristics, generation rates, recombination rates, electron concentrations, and hole concentrations have been calculated. The findings indicate the importance of selecting a suitable ETL to optimize PSC performance.