Potential-dependent structures investigated at the perchloric acid solution/iodine modified Au(111) interface by electrochemical frequency-modulation atomic force microscopy.
Potential-dependent structures investigated at the perchloric acid solution/iodine modified Au(111) interface by electrochemical frequency-modulation atomic force microscopy.
复制标题
通过电化学调频原子力显微镜研究高氯酸溶液/碘修饰的 Au(111) 界面的电势依赖性结构。
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
K. Fukui
中科院分区：
文献类型：
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作者：
T. Utsunomiya;Shoko Tatsumi;Y. Yokota;K. Fukui
采用电化学调频原子力显微镜（EC-FM-AFM）分析了碘修饰的Au（111）与高氯酸溶液之间的带电界面。电极的原子分辨率成像强烈依赖于电化学窗口内的电极电位：每个碘原子在电极电位的阴极范围内成像，而不是在更阳极的范围内成像，在相同的成像参数下，与阴极情况相比，尖端收缩了大约0.1 nm。在碘电极上获得的双电层区域的频移与尖端到样品的距离曲线表明，在无法获得原子分辨率图像的阳极电位下，水结构变弱，并在原始阴极电位下立即恢复。可逆水化结构与可逆地形图像和循环伏安法结果一致。这些结果表明，在这些条件下，高氯酸盐阴离子浓度在阳极电位下影响了界面水化，但没有对界面产生不可逆的变化。
Electrochemical frequency-modulation atomic force microscopy (EC-FM-AFM) was adopted to analyze the electrified interface between an iodine modified Au(111) and a perchloric acid solution. Atomic resolution imaging of the electrode was strongly dependent on the electrode potential within the electrochemical window: each iodine atom was imaged in the cathodic range of the electrode potential, but not in the more anodic range where the tip is retracted by approximately 0.1 nm compared to the cathodic case for the same imaging parameters. The frequency shift versus tip-to-sample distance curves obtained in the electric double layer region on the iodine adlayer indicated that the water structuring became weaker at the anodic potential, where the atomic resolution images could not be obtained, and immediately recovered at the original cathodic potential. The reversible hydration structures were consistent with the reversible topographic images and the cyclic voltammetry results. These results indicate that perchlorate anions concentrated at the anodic potential affect the interface hydration without any irreversible changes to the interface under these conditions.