Slow and Fast Dynamics at the Ionic Liquid/Gold Electrode Interface Separately Probed by Electrochemical Surface Plasmon Resonance Combined with Sequential Potential Pulse Techniques
Slow and Fast Dynamics at the Ionic Liquid/Gold Electrode Interface Separately Probed by Electrochemical Surface Plasmon Resonance Combined with Sequential Potential Pulse Techniques
复制标题
电化学表面等离激元共振结合顺序电位脉冲技术分别探测离子液体/金电极界面的慢速和快速动力学
DOI：
10.1149/1945-7111/ac58c4
复制
发表时间：
2022
影响因子：
3.9
通讯作者：
Nishi Naoya
中科院分区：
文献类型：
--
作者：
Zhang Shiwei;Sakka Tetsuo;Nishi Naoya
为了研究离子液体（IL）界面结构动力学的电位依赖性，将电化学表面等离子体共振（ESPR）技术与普通脉冲和差分脉冲技术相结合，在1-丁基-3-甲基咪唑双（三氟甲磺酰基）酰胺的金电极界面上进行了研究. SPR角在0.1 ~ 0.2 s内的快速响应，源于第一离子层中离子的取向、畸变和电子极化，这与电位变化和慢响应的方向相反。快速和慢速响应的这种单独检测是基于这样的事实实现的，即导致慢速响应的离子重排在短电位脉冲中不进行，特别是对于正脉冲。反映界面介电常数的快速响应表现出依赖于电位的介电饱和，即钟形（或骆驼形）的电位依赖性，在零电荷电位（PZC）附近达到最大值，在远离PZC的电位处急剧下降。分子动力学模拟解释了这种下降是由于第一离子层中的强电场和离子拥挤阻碍了离子的取向和畸变。
To investigate the potential dependence of the dynamics of the interface structure of an ionic liquid (IL), electrochemical surface plasmon resonance (ESPR) has been combined with normal pulse and differential pulse techniques at the gold electrode interface of 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) amide. The fast response of SPR angle in 0.1∼ 0.2 s, originating from the orientation, distortion, and electronic polarization of ions in the first ionic layer, has been clearly observed, which is opposite to both the direction of the change in potential and of the slow response. This separate detection of the fast and slow responses has been realized based on the fact that the ionic rearrangement, which results in the slow response, does not proceed in a short potential pulse, especially for the positive pulse. The fast response, which reflects the interfacial dielectric constant, exhibits the potential-dependent dielectric saturation, ie, a bell shape (or camel shape) potential dependence with a maximum around the potential of zero charge (PZC) and steep decrease at the potentials far from PZC. Molecular dynamics simulation explains that the decrease is caused by the strong electric field and ionic crowding in the first ionic layer which hinders the orientation and distortion of ions.