Study of ultramicroelectrode-based-measurement system for polymer electrolyte/electrocatalyst interface

基于超微电极的聚合物电解质/电催化剂界面测量系统研究

基本信息

批准号：
13450349
负责人：
UCHIDA Isamu
金额：
$ 9.73万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

Electrochemical measurement system for polymer electrolyte membrane/electrocatalyst layered structure, where the three-electrode system was difficult to apply so far, has been constructed by creating a series of ultramicroelectrodes. The system successfully enabled us to evaluate the interfacial electrochemical reaction based on a small-current-induced small iR drop even in the high resistivity medium. In addition, microarray electrode revealed a reaction mechanism of the electrocatalytic process. Consequently, electrochemical measurement system for polymer electrolyte fuel cell (PEFC) has been developed. Main research results are summarized as follows. First, an integrated ultramicroelectrode has been fabricated which involves working, counter and reference microelectrodes at a tip of a glass capillary. By using this, the gas phase electrochemical reactions were measured for hydrogen and methanol oxidation. Second, ionic conductivity of polymer electrolyte membrane has been measured employing an interdigitated microarray electrode by changing a water:methanol mixture ratio. Which is worthwhile for an operation of direct methanol fuel cell (DMFC). Third, by utilizing the interdigitated microarray electrode, methanol oxidation intermediate, which could not recorded at a conventional rotating ring-disk electrode, has been detected for the first time. Next, a porous microelectrode has been made which has a microcavity at the tip to measure electrochemical properties of particulate materials. This allowed a conventional evaluation of electrocatalysts in a powder form. Finally, a porous microring electrode, which has polymer electrolyte/electrocatalyst layered structure at the tip, has been created for a purpose to appraise a membrane electrode assembly (MEA) electrochemically. In conclusion. By designing and fabricating novel ultramicroelectrodes, electrochemical characterization for polymer electrolyte membrane/electrocatalyst structure has been greatly progressed.

通过创建一系列的超大型电极，已经构建了一系列的超大型电极，用于到目前为止，三电极系统难以应用的聚合物电解质膜/电催化剂分层结构的电化学测量系统。该系统成功地使我们能够基于小电流诱导的小型IR滴度评估界面电化学反应，即使在高电阻率介质中也是如此。此外，微阵列电极揭示了电催化过程的反应机理。因此，已经开发了聚合物电解质燃料电池（PEFC）的电化学测量系统。主要研究结果总结如下。首先，已经制造了一个集成的超大电极，涉及在玻璃毛细管的尖端上工作，反和引用微电极。通过使用这种情况，测量了气相电化学反应的氢和甲醇氧化。其次，通过更换水：甲醇混合物比，使用互嵌小阵列电极的聚合物电解质膜的离子电导率已经测量。对于直接甲醇燃料电池（DMFC）的操作是值得的。第三，首次检测到通过利用互插的微阵列电极，无法在常规的旋转环盘电极上记录的甲醇氧化中间体。接下来，已经制作了多孔微电极，该微电极在尖端上具有微腔，以测量颗粒材料的电化学性质。这允许以粉末形式对电催化剂进行常规评估。最后，已创建了一个在尖端的聚合物/电催化剂分层结构的多孔微孔电极，目的是为了评估膜电极组件（MEA）的电化学。综上所述。通过设计和制造新型的超大型电极，对聚合物电解质膜/电催化剂结构的电化学表征已得到很大的进展。