Microfluidic and Surface Electrochemistry

微流体和表面电化学

• 批准号: 37035-2012
• 负责人: Harrington, David
• 金额: $ 2.55万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568791
• 关键词: Microfluidic; Surface; Electrochemistry

This research is directed at an understanding of reactions of oxidation of fuels such as formic acid, methanol, ethanol or glycerol. These are all fuels that can be produced from biological sources, and so using them in fuel cells can lead to a sustainable energy system that is carbon neutral. A knowledge of what is happening at the molecular level enables improvement of electrochemical devices such as fuel cells whose operation occurs via reactions occurring on an electrode surface. These reactions are more complicated than for the more established hydrogen oxidation used in hydrogen fuel cells, because there are several surface species involved and there are side-reactions that give undesired soluble products. We will develop new methods to identify these species, determine how much of them there are, and exactly how they interconvert. We will use microfluidic electrochemistry techniques to characterize the complex chemistry. In the simplest variation, the molecules are flowed down a very thin channel where they pass electrodes at different voltages. The first electrode carries out the reaction, and the downstream ones act as detectors, capturing and counting the molecules produced at the first electrode. Because the channel is very thin, the capture is very efficient and the detection process is very sensitive. In addition we will use the electrochemical quartz-crystal microbalance (EQCM), which can sensitively and rapidly measure the masses of the molecules on the surface (and therefore their amounts). The combination of EQCM with microfluidics will enable the details of these reaction to be interpreted. The analysis will be enhanced by using impedance methods, which have two advantages: they can simultaneously measure processes happening on different time scales, and can measure without significantly changing the systems being measured.

这项研究旨在了解甲酸、甲醇、乙醇或甘油等燃料的氧化反应。这些都是可以从生物来源生产的燃料，因此在燃料电池中使用它们可以带来一个碳中性的可持续能源系统。对分子水平上正在发生的事情的了解有助于改进诸如燃料电池等电化学设备，这些设备的运行是通过电极表面发生的反应来进行的。这些反应比氢燃料电池中使用的更成熟的氢氧化反应更复杂，因为涉及到几个表面物种，并且存在产生不希望看到的可溶性产物的副反应。我们将开发新的方法来识别这些物种，确定它们有多少，以及它们到底是如何相互转换的。 我们将使用微流控电化学技术来表征复杂的化学。在最简单的变化中，分子沿着一个非常细的通道流动，在那里它们以不同的电压通过电极。第一个电极进行反应，下游的电极充当检测器，捕获并计数第一个电极产生的分子。由于通道很细，捕获效率很高，检测过程非常灵敏。此外，我们将使用电化学石英晶体微天平(EQCM)，它可以灵敏而快速地测量表面分子的质量(因此也就是它们的数量)。EQCM与微流控技术的结合将使人们能够解释这些反应的细节。通过使用阻抗方法来加强分析，这种方法有两个优点：可以同时测量在不同时间尺度上发生的过程，并且可以在不显著改变被测系统的情况下进行测量。