van Spronsen Matthijs A, Zhao Xiao, Jaugstetter Maximilian, Escudero Carlos, Duchoň Tomáš, Hunt Adrian, Waluyo Iradwikanari, Yang Peidong, Tschulik Kristina, Salmeron Miquel B
Diamond Light Source Ltd., Didcot OX11 0DE, U.K.
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
J Phys Chem Lett. 2021 Oct 21;12(41):10212-10217. doi: 10.1021/acs.jpclett.1c02115. Epub 2021 Oct 14.
To understand corrosion, energy storage, (electro)catalysis, etc., obtaining chemical information on the solid-liquid interface is crucial but remains extremely challenging. Here, X-ray absorption spectroscopy (XAS) is used to study the solid-liquid interface between TiO and HO. A thin film (6.7 nm) of TiO is deposited on an X-ray-transparent SiN window, acting as the working electrode in a three-electrode flow cell. The spectra are collected based on the electron emission resulting from the decay of the X-ray-induced core-hole-excited atoms, which we show is sensitive to the solid-liquid interface within a few nm. The drain currents measured at the working and counter electrodes are identical but of opposite sign. With this method, we found that the water layer next to anatase is spectroscopically similar to ice. This result highlights the potential of electron-yield XAS to obtain chemical and structural information with a high sensitivity for the species at the electrode-electrolyte interface.
为了理解腐蚀、能量存储、（电）催化等过程，获取固液界面的化学信息至关重要，但仍极具挑战性。在此，采用X射线吸收光谱法（XAS）研究TiO₂与H₂O之间的固液界面。在X射线透明的SiN窗口上沉积一层6.7 nm厚的TiO₂薄膜，作为三电极流动池中工作电极。光谱是基于X射线诱导的芯孔激发原子衰变产生的电子发射收集的，我们发现这对几纳米范围内的固液界面敏感。在工作电极和对电极处测得的漏电流大小相同但符号相反。通过这种方法，我们发现锐钛矿旁边的水层在光谱上与冰相似。这一结果凸显了电子产率XAS在获取电极 - 电解质界面物种的化学和结构信息方面具有高灵敏度的潜力。
