Temporally and Spatially Resolved Electrochemical Infrared Spectroscopy

电化学对人类活动和全球经济具有重要的价值和意义。例如，包括电池、染料敏化太阳能电池、燃料电池和超级电容器在内的电力来源都需要电化学过程来发电。此外，许多工业实践依靠电催化转化来制造有价值的商品化学品和材料。基础研究，导致更好的理解和更有效的手段来执行电化学反应将是巨大的社会效益，因为据估计，电化学活动消耗约10%的世界电能。与商业上重要的反应机制有关的信息传统上是从测量电特性（如电流-电压关系）的技术中推断出来的。使用纯电学方法研究电化学反应的一个缺点是缺乏化学敏感性，因此光谱学（电磁辐射与原子和分子的相互作用）可以与传统方法相结合，以获得分子水平的信息。该研究项目旨在通过将传统电化学技术与先进的红外光谱技术相结合来了解电化学反应的新信息。我们提出的研究目标是创造一种表面，可以将来自极少数分子的红外信号放大许多数量级，这样我们就可以测量和量化在电化学转化（如燃料电池中的燃料氧化）过程中发生的化学物质和反应。例如，我们建议利用加拿大唯一的同步加速器设施（位于SK萨斯卡通的加拿大光源）产生的红外辐射的独特特性，在1/100,000秒的时间尺度上跟踪分子的命运。这一信息是非常重要的，因为电催化材料的性能可能会受到非常短的中间体的不利影响。确定哪些中间体存在以及电化学反应最终产物的分布将使我们能够评估现有电催化材料的性能，并帮助设计新的和改进的材料，以实现更有效的电化学反应。

Electrochemistry is of great value and importance to human activity and the global economy. For example, electrical power sources including batteries, dye-sensitized solar cells, fuels cells and supercapacitors all require electrochemical processes to generate electricity. Furthermore, many industrial practices rely on electrocatalytic transformations to manufacture valuable commodity chemicals and materials. Fundamental studies that lead to better understanding and more efficient means to perform electrochemical reactions would be of great societal benefit as it is estimated that electrochemical activities consume about 10% of the world’s electrical energy. Information pertaining to commercially important reaction mechanisms has traditionally been inferred from techniques that measure electrical characteristics (e.g. current- voltage relationships). A deficiency of using purely electrical methods to study electrochemical reactions is the lack of chemical sensitivity they provide and for this reason spectroscopy (the interaction of electromagnetic radiation with atoms and molecules) can be combined with traditional methods to gain molecular-level information. This research program seeks to learn new information about electrochemical reactions through the coupling of traditional electrochemical techniques with advanced infrared (IR) spectroscopy techniques. Our proposed research aims to create surfaces that amplify the IR signal from a very small number of molecules by many orders of magnitude so that we can measure and quantify what chemical species and reactions occur during electrochemical transformations such as the oxidation of fuels in fuel cells. For example, we are proposing to use the unique properties of IR radiation generated at Canada’s only synchrotron facility (the Canadian Light Source located in Saskatoon, SK) to follow the fate of molecules on the time scale of 1/100,000 of a second. This information is very important as the performance of electrocatalytic materials can be adversely affected by very short-lived intermediates. Identifying which intermediates exist and the distribution of the final products of electrochemical reactions will allow us to assess the performance of existing electrocatalytic materials and help design new and improved materials for more efficient electrochemical reactions.