The exchange of ions in hybrid organic–inorganic perovskites with the general formula APbX₃ (A = MA, FA; X = I, Cl, Br) is studied in five different systems using in situ real-time grazing incident X-ray diffraction (GIXD). In systems where the organic cation is exchanged, we find a continuous shift of the lattice parameter. The relative shift compared to the pure materials is used to quantify the exchange. Whether or not a conversion is possible, as well as the amount of exchanged cations, depends on the halide used. In the case of the interconversion of MAPbI₃ and MAPbCl₃, we observe a decay of the diffraction peaks of the original perovskite and the emergence of new peaks corresponding to the structure with the alternative halide. Moreover, we determined the relevant time scales of the growth and decay of the perovskite structures.

中文翻译：

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原位实时X射线散射研究有机-无机钙钛矿杂化薄膜中离子交换反应的动力学

在五个不同的系统中，使用原位实时掠入射X射线衍射仪（通式为APbX ₃（A = MA，FA; X = I，Cl，Br））研究了杂化有机-无机钙钛矿中的离子交换。GIXD）。在交换有机阳离子的系统中，我们发现晶格参数连续变化。与纯材料相比的相对位移用于量化交换。能否进行转化以及交换的阳离子量取决于所用的卤化物。在MAPbI ₃和MAPbCl ₃相互转化的情况下，我们观察到了原始钙钛矿衍射峰的衰减以及与替代卤化物结构相对应的新峰的出现。此外，我们确定了钙钛矿结构生长和衰减的相关时间尺度。