Lead-free or low lead content perovskite materials are explored in photovoltaic (PV) devices to mitigate the challenges of toxic lead-based halides. However, the conversion efficiency from such materials is far below compared to its counterparts. Therefore, to make a humble contribution in the development of lead-free or low lead content perovskite solar cells (PSCs) for future thin-film PV technology, a simulation study of tin (Sn) and Pb mixed halide (MAPb_0.5Sn_0.5I₃, 1.22 eV) PSC is carried out in this manuscript. The device is further optimized in terms of transport layer and thickness variation to get 15.1% conversion efficiency. Moreover, the optimized narrow bandgap halide based device is further deployed in the monolithic tandem configuration with lead-free wide bandgap (1.82 eV) halide, i.e. Cs₂AgBi_0.75Sb_0.25Br₆, 1.82 eV (WBH) PSC, to mitigate the thermalization as well as transparent E _g losses. Filtered spectrum, current matching, and construction of tandem J–V curve at the current matching point are utilized to design the tandem solar cell under consideration. Tandem device delivered short current density, J _SC (15.21 mA cm⁻²), open-circuit voltage, V _OC (1.95 V), fill factor, FF (74.09%) and power conversion efficiency, PCE (21.97%). The performance of the devices considered in this work is found to be in good approximation with experimental work.

中文翻译：

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利用无铅和低铅卤化物钙钛矿的 22% 高效全钙钛矿串联太阳能电池的数值模拟

在光伏 (PV) 设备中探索无铅或低铅含量钙钛矿材料，以减轻有毒铅基卤化物的挑战。然而，与同类材料相比，此类材料的转换效率远低于此。因此，为了在未来薄膜光伏技术的无铅或低铅含量钙钛矿太阳能电池 (PSC) 的开发中做出微薄的贡献，对锡 (Sn) 和 Pb 混合卤化物 (MAPb _0.5 Sn _0.5 I ) 的模拟研究₃, 1.22 eV) PSC 在本手稿中进行。该器件在传输层和厚度变化方面进一步优化，获得 15.1% 的转换效率。此外，优化的窄带隙卤化物器件进一步部署在单片串联配置中，采用无铅宽带隙 (1.82 eV) 卤化物，即 Cs ₂ AgBi _0.75 Sb _0.25 Br ₆ , 1.82 eV (WBH) PSC，以减轻热化以及透明的乙 _g损失。滤波频谱、电流匹配和串联结构Ĵ–五电流匹配点的曲线用于设计所考虑的串联太阳能电池。串联器件提供短电流密度，Ĵ _SC (15.21 mA cm ^-2 )，开路电压，五 _OC (1.95 V)，填充因子，FF (74.09%) 和功率转换效率，PCE (21.97%)。发现在这项工作中考虑的设备的性能与实验工作非常接近。