Time‐resolved X‐ray absorption spectroscopy (XAS) offers the possibility to monitor the state of materials during chemical reactions. While this technique has been established for transmission measurements for a number of years, XAS measurements in fluorescence mode are challenging because of limitations in signal collection as well as detectors. Nevertheless, measurements in fluorescence mode are often the only option to study complex materials containing heavy matrices or in samples where the element of interest is in low concentration. Here, it has been demonstrated that high‐quality quick‐scanning full extended X‐ray absorption fine‐structure data can be readily obtained with sub‐second time resolution in fluorescence mode, even for highly diluted samples. It has also been demonstrated that in challenging samples, where transmission measurements are not feasible, quick fluorescence can yield significant insight in reaction kinetics. By studying the fast high‐temperature oxidation of a reduced LaFe_0.8Ni_0.8O₃ perovskite type, an example where the perovskite matrix elements prevent measurements in fluorescence, it is shown that it is now possible to follow the state of Ni in situ at a 3 s time resolution.

中文翻译：

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荧光检测快速扫描X射线吸收光谱。

时间分辨X射线吸收光谱（XAS）提供了在化学反应过程中监视材料状态的可能性。尽管已经建立了用于传输测量的技术多年，但是由于信号收集和检测器的局限性，荧光模式下的XAS测量具有挑战性。但是，荧光模式下的测量通常是研究包含重基质或目标元素浓度低的样品的复杂材料的唯一选择。此处已证明，即使对于高度稀释的样品，也可以在亚秒级的时间分辨率下以荧光模式轻松获得高质量的快速扫描的完整扩展X射线吸收精细结构数据。还已经证明，在具有挑战性的样本中，在透射测量不可行的地方，快速荧光可以对反应动力学产生重要的了解。通过研究还原的LaFe的快速高温氧化_0.8 Ni _0.8 O ₃钙钛矿型，钙钛矿基质元素阻止荧光测量的实例，表明现在可以3 s的时间分辨率原位追踪Ni的状态。