Structural Dynamics of the Electrical Double Layer during Capacitive Charging/Discharging Processes
Structural Dynamics of the Electrical Double Layer during Capacitive Charging/Discharging Processes
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DOI：
10.1021/jp506979p
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发表时间：
2014-09
影响因子：
3.7
通讯作者：
Masashi Nakamura;Hiroto Kaminaga;O. Endo;H. Tajiri;O. Sakata;Nagahiro Hoshi
中科院分区：
文献类型：
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作者：
Masashi Nakamura;Hiroto Kaminaga;O. Endo;H. Tajiri;O. Sakata;Nagahiro Hoshi
利用时间分辨x射线衍射测定了Ag（100）电极在CsBr溶液中双层充放电过程中Cs+在外层亥姆霍兹平面（OHP）上的过渡结构。在Ag（100）上形成c(2 × 2)-Br的双层电位区，瞬态电流由两个不同时间尺度的指数项组成：快速和慢速分别是由于水分子的介电极化和Cs+的转移引起的。慢项由充电和放电过程中Cs+的不同动态过程组成。当电位向正方向阶跃时，OHP处Cs+的覆盖率减小。在这一步中，对OHP结构敏感的（0 0 1）反射处的瞬态x射线强度表明，Cs+从OHP中按时间的指数函数释放出来。x射线瞬态强度衰减具有与当前瞬态测量相似的时间尺度。另一方面，……
Transitional structures of Cs+ at the outer Helmholtz plane (OHP) have been determined using time-resolved X-ray diffraction during the double-layer charging/discharging on the Ag(100) electrode in CsBr solution. At the double-layer potential region at which c(2 × 2)-Br is formed on Ag(100), the transient current comprises two exponential terms with different time scales: a rapid and a slow one are due to the dielectric polarization of water molecules and the transfer of Cs+, respectively. The slow term is composed of different dynamic processes of Cs+ during charging and discharging. When the potential is stepped in the positive direction, the coverage of Cs+ at the OHP decreases. In this step, the transient X-ray intensity at the (0 0 1) reflection, which is sensitive to the OHP structure, shows that Cs+ is released from the OHP according to exponential function of time. The decay of transient intensity of X-ray has a time scale similar to that of the current transient measurement. On the other hand, th...