Design & Optimization of a Lead-Free High Performance Cs₂SnI₆ - Based Inorganic Perovskite Solar Cell by SCAPS-1D.

abstract- Due to rising global energy consumption, renewable energy is essential. Solar photovoltaic technology is a viable and eco-friendly alternative to fossil fuels. Perovskite-based thirdgeneration solar cells are gaining popularity for their efficiency and lower cost. This research evaluates inorganic perovskite solar cells using eco-friendly, tin-halide Cs<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>SnI<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup>-based perovskite, a non-toxic alternative to lead-based perovskite cells. Simulations with SCAPS-1D software explored different layer configurations, including various ETLs ($\mathrm{ZnO}, \mathrm{C d S}, \mathrm{TiO}_{2}, \mathrm{Z n S e}$), HTLs (PEDOT, Spiro-OMeTAD, P3HT, CZTSe, CuSCN, CuI, MoO 3), and back metal contacts ($\mathrm{Cu}, \mathrm{Ag}, \mathrm{Fe}, \mathrm{C}, \mathrm{Au}, \mathrm{Ni}$). $\mathrm{Cs}_{2} \mathrm{SnI}_{6}, \mathrm{ZnSe}^{2}, \mathrm{MoO}_{3}$, and Ni were found optimal for stable, efficient inorganic perovskite cells. The current investigation introduces a novel architectural design, namely, $\mathrm{FTO} / \mathrm{ZnSe}^{2} / \mathrm{Cs}_{2} \mathrm{SnI}_{6} / \mathrm{MoO}_{3} / \mathrm{Ni}$, which exhibits remarkable device performance with a power conversion efficiency of 28.79%, a short-circuit current (Jsc) of 27.157 $\mathrm{mA} / \mathrm{cm}^{2}$, an open-circuit voltage (Voc) of 1.34 V, and a fill factor (FF) of {79.33%}. The suggested structure exhibits a high level of concurrence to the current experimental findings and it is suitable for forthcoming lead-free and tin-halide-based inorganic perovskite solar cells (PSCs).