The compositional engineering of an organo-lead halide perovskite plays a crucial role in determining the versatility and stability of photovoltaic device performance, which is vital for its commercialization. Manipulating the ion composition of the perovskite ABX₃ crystal structure within a reasonable tolerance factor range allows for achieving tunable bandgaps and material stability. While perovskite solar cells have shown comparable performance to silicon crystalline solar cells, research groups pay little attention to the stoichiometry of the final perovskite film. The precise manipulation of perovskite's chemical composition is critical in determining its cell reproducibility. The UV-Vis spectrophotometer is a potent and widely used instrument for distinguishing precursors in solutions in various fields. Herein, we report for the first time that UV-Vis spectra are an applicable tool in determining the formulation of perovskite films. We demonstrate a successful method for separating the organic and inorganic components of the perovskite film, establishing calibration curves, and performing detailed calculations. Our findings reveal that the chemical composition of perovskite films does not match the proportion of the precursor solutions. This study could lay the groundwork for future research on quantifying perovskite films and explaining the high reproducibility trends observed in perovskite solar cells.

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混合阳离子、混合卤化物铅钙钛矿薄膜及其前驱体溶液之间化学计量偏差的研究

有机铅卤化物钙钛矿的组成工程在决定光伏器件性能的多功能性和稳定性方面起着至关重要的作用，这对其商业化至关重要。在合理的公差因子范围内控制钙钛矿 ABX ₃晶体结构的离子组成可以实现可调节的带隙和材料稳定性。虽然钙钛矿太阳能电池已表现出与硅晶体太阳能电池相当的性能，但研究小组很少关注最终钙钛矿薄膜的化学计量。钙钛矿化学成分的精确控制对于确定其细胞再现性至关重要。紫外-可见分光光度计是一种有效且广泛使用的仪器，可用于区分各个领域溶液中的前体。在此，我们首次报告紫外-可见光谱是确定钙钛矿薄膜配方的适用工具。我们展示了一种成功的方法来分离钙钛矿薄膜的有机和无机成分、建立校准曲线并进行详细计算。我们的研究结果表明，钙钛矿薄膜的化学成分与前驱体溶液的比例不匹配。这项研究可以为未来量化钙钛矿薄膜和解释钙钛矿太阳能电池中观察到的高再现性趋势的研究奠定基础。