Tandem solar cells (TSCs) based on metal halide perovskites offer a route to increase power conversion efficiency (PCE). However, there are limited options for narrow-bandgap bottom subcells. Colloidal quantum dots-based solar cells are found attractive for this role. Herein, a cost-effective two-terminal (2T) monolithic TSC structure consisting of wide-bandgap all-inorganic perovskite ${\text{CsPbI}}_3$ top subcell and narrow-bandgap chalcogenide PbS quantum dots bottom subcell is proposed. For optimization of the PCE of the tandem structure, standalone and tandem analysis are done in terms of variation of absorber layer thickness, total defect density, interfacial defect density, back metal contact, current density voltage (J–V) curves, external quantum efficiency, current matching, and tandem photovoltaic parameters. Optimized TSCs designed with the 530 nm/450 nm-thick absorber layers of top/bottom sub cells result in $J_{\text{SC}}$ of 19.28 mA cm⁻², $V_{\text{OC}}$ of 1.89 V, and PCE of 27.32%. It is found that performance of the device is very sensitive to the total defect density of the bottom subcell. Therefore, high PCE can be obtained by controlling the total defect density of the bottom subcell. This work motivates the experimental realization of low-cost, high-efficiency TSCs for further research.

中文翻译：

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通过太阳能电池电容模拟器 1D 优化钙钛矿/胶体量子点单片串联太阳能电池以增强器件性能

基于金属卤化物钙钛矿的串联太阳能电池（TSC）提供了提高电力转换效率（PCE）的途径。然而，窄带隙底部子电池的选择有限。人们发现基于胶体量子点的太阳能电池对于这一作用很有吸引力。本文提出了一种由宽带隙全无机钙钛矿组成的经济高效的两端（2T）单片 TSC 结构${\text{碘化铯}}_3$提出了顶部子电池和窄带隙硫族化物PbS量子点底部子电池。为了优化串联结构的 PCE，根据吸收层厚度的变化、总缺陷密度、界面缺陷密度、背面金属接触、电流密度电压 ( J – V ) 曲线、外部量子效率进行独立和串联分析、电流匹配和串联光伏参数。采用 530 nm/450 nm 厚的顶部/底部子电池吸收层设计的优化 TSC 导致$J_{\text{SC}}$19.28 mA cm ^-2，$V_{\text{奥克}}$1.89 V，PCE 27.32%。研究发现，器件的性能对底部子电池的总缺陷密度非常敏感。因此，通过控制底部子电池的总缺陷密度可以获得高PCE。这项工作促进了低成本、高效率 TSC 的实验实现，以供进一步研究。