Advanced Infrared Spectroscopy and Imaging of Electrochemical and Chemical Reactions

这项正在进行的研究计划的长期目标是通过开发先进的红外光谱和成像能力，对电化学界面和反应产生新的科学理解。现代社会需要越来越有效的手段来化学储存、发电和利用电力进行人类活动。实际应用包括电池、燃料电池、电化学处理和金属回收。在基本层面上，所有这些过程都涉及一个或多个界面，在这些界面上，电场驱动电子、分子和离子重新分布，这是潜在的物理和化学操作的组成部分。尽管这些界面很重要，但关于组成动态电化学表面的化学物种的结构，如浸泡在溶液中的固体电极，仍有许多未知之处。提取关键的理解水平需要应用提供分子水平信息的原位技术。这项研究计划寻求提高一类此类技术(表面增强振动光谱)的灵敏度，并利用改进的方法来创造关于电化学界面的新知识。例如，我们正在探索光-物质相互作用的基本原理，以了解如何使用表面增强振动光谱产生能够从极少数分子中提供可识别信号的界面。我们还使用加拿大唯一的同步加速器设施(位于萨斯喀彻温省萨斯卡通的加拿大光源)产生的独特红外辐射源，在1/100,000秒的时间尺度上跟踪电极表面分子的命运。我们的方法进步不仅促进了对带电界面的基础研究的更大能力，而且还带来了化学传感和分子识别的改进能力。

The long-term objective of this on-going research program is generation of new scientific understanding of electrochemical interfaces and reactions through the development of advanced infrared spectroscopy and imaging capabilities. Modern society requires ever increasingly efficient means to chemically store, generate and utilize electricity for anthropogenic activity. Practical applications include batteries, fuel cells, electrochemical processing and metal recovery. At the fundamental level, all of these processes involve one or more interfaces where electric fields drive electronic, molecular and ionic redistributions integral to underlying physical and chemical manipulations. Despite the importance of these interfaces, much remains unknown about the structure of the chemical species that comprise a dynamic electrochemical surface such as a solid electrode immersed in a solution. Extracting key levels of understanding requires application of in situ techniques that provide information on the molecular level. This research program seeks to both advance the sensitivity of a class of such techniques (surface enhanced vibrational spectroscopy) and exploit improved methodologies to create new knowledge of electrochemical interfaces. For example, we are exploring the fundamentals of light-matter interactions to understand how to produce interfaces capable of providing discernible signals from very small numbers of molecules using surface enhanced vibrational spectroscopy. We also use unique sources of infrared radiation generated at Canada's only synchrotron facility (the Canadian Light Source located in Saskatoon, Saskatchewan) to follow the fate of molecules at electrode surfaces on the time scale of 1/100,000 of a second. Our methodological advances not only spur greater capabilities for fundamental studies of electrified interfaces but also introduce improved capabilities for chemical sensing and molecular recognition.