Gold Electrocatalysts for Alkaline Media

这个小型企业创新研究(SBIR)第二阶段项目是在分析和表面化学的一般领域，以及在电化学和材料化学的子领域。这项活动的目标是开发高分散、小颗粒、负载型目标电催化剂，用于在碱性介质中还原氧气。在之前的第一阶段研究中，得到了美国国家科学基金会ISI-8660688的资助，物理科学公司证明，氧气直接电还原成水的过程在目标100表面得到了增强。该公司进一步证明，可以在碳载体上制造小颗粒金催化剂，使用这些电催化剂可以减少不需要的过氧化氢电还原产物的形成。在目前的第二阶段活动中，前一阶段的工作正在扩大和扩大范围。目前的研究任务包括：(1)制备高度分散的负载型金电催化剂和开发用于碱性介质的耐蚀载体材料；(2)通过改变颗粒尺寸和制备条件来调整金微晶结构，以制备(100)择优取向的金粒子；(3)在真空和实际运行的燃料电池中使用扩展X射线吸收精细结构(EXAFS)光谱测定金颗粒的微晶结构；(4)在实际运行条件下测量半电池配置中的电极性能。从这项研究中衍生出的新型电催化剂可能会有广泛的、技术上重要的应用。

This Small Business Innovation Research (SBIR) Phase II project is in the general area of analytical and surface chemistry and in the subfields of electrochemistry and materials chemistry. The goal of this activity is the development of highly dispersed, small particle, supported goal electrocatalysts for the reduction of dioxygen in alkaline media. In the preceding Phase I research which was supported under NSF grant ISI-8660688, Physical Sciences, Inc. demonstrated that the direct electroreduction of dioxygen to water was enhanced on the 100 surface of goal. The company further demonstrated that small-particle gold catalysts could be fabricated on carbon supports, and that the use of these electrocatalysts gave rise to diminished formation of the undesired hydrogen peroxide electroreduction product. In the present Phase II activity, the previous Phase I work is being extended and broadened in scope. Research tasks for the current effort include (1) preparation of highly dispersed supported gold electrocatalysts and development of corrosion resistant support materials for use in alkaline media; (2) tailoring of the gold crystallite structure through variation of both particle size and fabrication conditions to produce (100) preferentially oriented gold particles; (3) determination of the crystallite structure of the gold particles using extended x-ray absorption fine structure (EXAFS) spectroscopy both in vacuo and in situ in an actual operating fuel cell; and (4) measurement of electrode performance in a half-cell configuration under realistic operating conditions. The new electrocatalysts derived from this research could have broad, technologically important applications.