Organic-inorganic halide perovskites have been identified as favorable candidates for the next generation of photovoltaics. Adding alkali metal halides to perovskite films has been shown to be a viable option to improve the perovskite film quality and to modulate their fundamental properties. In this work, we perform optical and electron-beam based characterizations of mixed Sn/Pb based perovskite films to investigate the effect of the addition of the alkaline metal halide SrI₂. By analyzing structural (X-ray diffraction), morphological (Scanning Electron Microscopy), optical (photoluminescence), and chemical properties (X-ray photoelectron spectroscopy), we show a complex interplay of effects upon addition of Sr²⁺ into the perovskite solution. Low concentrations of Sr²⁺ increases lattice strain, which hints at incorporation of the additive into the perovskite lattice and improves the film optoelectronic properties. As the additive concentration increases beyond 0.5 mol %, microstrain decreases. At concentrations >0.5 mol %, Sr²⁺ induces significant reduction of the average domain size, which impacts both structural and optical properties of the perovskite film.

有机-无机卤化物钙钛矿已被确定为下一代光伏的有利候选者。在钙钛矿薄膜中添加碱金属卤化物已被证明是提高钙钛矿薄膜质量和调节其基本性能的可行选择。在这项工作中，我们对混合 Sn/Pb 钙钛矿薄膜进行了基于光学和电子束的表征，以研究添加碱金属卤化物 SrI _{2 的影响}。通过分析结构（X 射线衍射）、形态（扫描电子显微镜）、光学（光致发光）和化学性质（X 射线光电子能谱），我们展示了将 Sr ^{2+ 添加}到钙钛矿溶液中后的复杂相互作用. 低浓度的 Sr ²⁺增加晶格应变，这暗示将添加剂掺入钙钛矿晶格并改善薄膜光电性能。随着添加剂浓度增加超过 0.5 mol%，微应变降低。在浓度 > 0.5 mol % 时，Sr ^{2+ 会}导致平均畴尺寸显着减小，这会影响钙钛矿薄膜的结构和光学特性。