| Co-Investigator(Kenkyū-buntansha) |
ITOH Takashi Tohoku University, Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (40302187)
MOHAMED Mohamedi Tohoku University, Graduate School of Engineering, Lecturer, 大学院・工学研究科, 講師 (60332516)
UMEDA Minoru Nagaoka University of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (20323066)
|
|---|
| Research Abstract |
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.
|
