Plasmon-Resonant Vibrational Sum Frequency Generation of Electrochemical Interfaces: Direct Observation of Carbon Dioxide Electroreduction on Gold
Plasmon-Resonant Vibrational Sum Frequency Generation of Electrochemical Interfaces: Direct Observation of Carbon Dioxide Electroreduction on Gold
复制标题
电化学界面的等离子共振振动和频率生成：金上二氧化碳电还原的直接观察
DOI：
10.1021/acs.jpca.0c04268
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Baker, L. Robert
中科院分区：
文献类型：
--
作者：
Wallentine, Spencer;Bandaranayake, Savini;Biswas, Somnath;Baker, L. Robert
在这里，我们提出了等离子体共振振动和频产生光谱用于电化学测量。利用表面等离子体共振，我们耦合光通过CaF 2棱镜的Au膜的>50 nm，以达到掩埋的Au/电解质界面。该方法使我们能够使用本体电解质和高电流密度（>1 mA/cm 2），因此适合于在相关电化学反应条件下探测活性中间体。菲涅耳因子模型的等离子体共振的三层系统（CaF 2/Au/电解质）显示出良好的协议与实验数据。与表面等离子体共振的偏角动量匹配使我们能够通过简单地扫描红外波长而无需任何角度重新对准来测量宽范围红外频率的官能团（−CH，−CD，−CN，−NO2）。此外，我们报告的检测限<1%的单层的Au/电解质界面。使用这种方法，我们观察到一个活跃的中间体在催化电流的Au上CO2还原。因此，我们相信这种方法将提供电化学反应的机理理解。
Here we present plasmon-resonant vibrational sum frequency generation spectroscopy for use in electrochemical measurements. Using surface plasmon resonance we couple light through a CaF2prism to Au films of >50 nm in order to reach the buried Au/electrolyte interface. The approach enables us to use bulk electrolyte, and high current densities (>1 mA/cm2), and therefore is suitable to probe active intermediates under relevant electrochemical reaction conditions. Fresnel factor modeling of the plasmon resonance for a three layer system (CaF2/Au/electrolyte) shows good agreement with experimental data. Off-angle momentum-matching to the surface plasmon resonance allows us to measure functional groups (−CH, −CD, −CN, −NO2) across a wide range of infrared frequencies by simply scanning the infrared wavelength without any angular realignment. Additionally we report a detection limit <1% of a monolayer for the Au/electrolyte interface. Using this method we observe an active intermediate during CO2reduction on Au at catalytic currents. Consequently, we believe that this method will provide mechanistic understanding of electrochemical reactions.