Constractional study of nano electrocatalysts for functionalization of three phase interface

平面电极与粉末电催化剂在燃料电池电极中的实际应用存在着巨大的差距。这是因为后一种结构由于其三维结构而比较复杂；纳米催化剂颗粒装载在导电的亚微米颗粒上。为了使含粉末电催化剂的三相界面功能化，我们开发了通过单独改变其大小和颗粒间距离来构建催化剂颗粒的方法。此外，还研究了所构建电极的电极反应。此外，还对膜电极组件（MEAs）和燃料电池进行了研究。例如：(1)模拟电催化剂的掩膜制备；(2)基于掩膜制备技术的Pt降解的原位SEM观察；(3)扫描电化学显微镜下O_2还原过程中H_2O_2副产物生成的研究；(4)直接甲醇燃料电池电极调节的改进；(5)甲醇和氧气存在下的反应选择性研究。因此，消除二维和三维电极之间大间隙的研究取得了很大进展。

A huge disparity exists between a planar electrode and a practical powder electrocatalyst for a utilization in fuel cell electrode. This is because that the latter structure is complicated owing to its three dimensional construction ; nano catalyst particles are loaded on electroconductive submicron particles. In order to functionalize the three phase interface containing the powder electrocatalyst, we developed to construct the catalyst particle by changing its size and interparticlar distance independently. In addition, electrode reactions using the constructed electrode were investigated. Moreover, investigations of membrane electrode assemblies(MEAs) and fuel cells using the powder catalysts were conducted. For instance, the following experiments were carried out :(1) mask fabrication of modeled electrocatalysts,(2) ex-situ SEM observation of Pt degradation based on the mask fabrication technique,(3) scanning electrochemical microscopy study of H_2O_2 byproduct generation during O_2 reduction,(4) an improvement of electrode conditioning at direct methanol fuel cell, and(5) reaction selective studies in the presence of methanol and oxygen. Consequently, an investigation to vanish the large gap between two and three dimensional electrodes was mostly progressed.