The oxygen evolution reaction (OER) on the TiO surface at the solid–liquid interface was observed in real-time and using fluorescence-yield X-ray absorption spectroscopy (XAS) in the soft X-ray region. The OER was observed during a potential sweep with UV light on or off, focusing on the oxygen K-edge XAS. Although conventional XAS measurements require long measurement times, the spectra during the reaction were obtained every 3 s in the present experiment via wavelength-dispersive XAS technique. An increase in the X-ray absorption intensity at approximately 533.8 eV was observed during the potential sweep only with UV light on. The observed spectral change is discussed in relation to the reaction mechanism of the OER. The present technique can be applied to a wide range of analyses of (photo-) electrocatalysis and electrochemical reactions at solid–liquid interfaces to observe their products and intermediates during the reaction.

中文翻译：

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软X射线吸收光谱实时操作观察TiO2光电催化中间体


利用软 X 射线区域的荧光 X 射线吸收光谱 (XAS) 实时观察 TiO 表面固液界面的析氧反应 (OER)。在开启或关闭紫外光的电位扫描过程中观察 OER，重点关注氧 K 边缘 XAS。虽然传统的 XAS 测量需要很长的测量时间，但在本实验中，通过波长色散 XAS 技术每 3 秒获得一次反应过程中的光谱。仅在开启紫外光的情况下进行电位扫描期间，观察到 X 射线吸收强度增加约 533.8 eV。讨论了观察到的光谱变化与 OER 反应机理的关系。本技术可应用于固液界面的（光）电催化和电化学反应的广泛分析，以观察反应过程中的产物和中间体。