Real-time observation of an electrochemical reaction at a solid–liquid interface was performed using fluorescence-yield wavelength-dispersive soft X-ray absorption spectroscopy (XAS). A dedicated electrochemical cell was prepared for this study. As a model experiment, an electrochemical oxygen evolution reaction (OER) was observed in alkaline solution (0.1 M NaOH) on the surface of a Pt thin film working electrode. With positive potential shift, the XAS signal at K-edge of oxygen, whose peak position is close to that of gas-phase O₂, increased in correlation with the electrode potential. This method has potential as a real-time observation method for time-dependent processes in various fields using electrochemical reactions at the solid–liquid interface, especially electrochemical catalytic reactions.

中文翻译：

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荧光产率波长色散软X射线吸收光谱法在固液界面电化学反应原位观测技术的发展

使用荧光产率波长色散软 X 射线吸收光谱 (XAS) 对固液界面处的电化学反应进行实时观察。为这项研究准备了专用的电化学电池。作为模型实验，在 Pt 薄膜工作电极表面的碱性溶液（0.1 M NaOH）中观察到电化学析氧反应（OER）。随着电位正移，氧的K边缘的XAS信号，其峰值位置接近气相O ₂的峰值位置，随着电极电位的增加而增加。该方法具有作为使用固-液界面电化学反应，尤其是电化学催化反应的各个领域的时间相关过程的实时观察方法的潜力。