对三金属合金催化剂的原子协调结构和增强的电催化活性之间的相关性
Bridgid N Wanjala1, Bin Fang, Jin Luo
1Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, United States.
Journal of the American Chemical Society
|June 30, 2011
概括
纳米工程PtNiFe/C催化剂显示了氧降解反应的温度依赖的电催化性能. 更高的温度通过更好的合金增强了特定活性,尽管白金表面度降低了.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 燃料电池依赖于高效的电催化剂,用于减少氧气等反应.
- 了解原子级结构-活性关系对于设计先进的催化剂至关重要.
研究的目的:
- 研究在不同温度下处理的PtNiFe/C催化剂的原子结构和电催化性能之间的相关性.
- 提供对影响燃料电池反应的合金和相互作用结构的基本见解.
主要方法:
- 旋转盘电极 (RDE) 和质子交换膜燃料电池 (PEMFC) 测试用于活动测量.
- 传输电子显微镜 (TEM),X射线衍射 (XRD),X射线光电子光谱 (XPS) 和X射线吸收细结构 (XAFS) 分析用于结构特征.
主要成果:
- 随着温度的增加,质量活动下降,而特异性活动增加.
- 在高温下,XAFS显示了增强的异原子协调和合金.
- 在高温下,XPS显示了表面Pt度的降低,这表明表面丰富和合金之间的权衡.
结论:
- 在较低温度下较高的质量活性归因于Pt表面丰富.
- 在高温下更高的特异性活性来自增强的Pt合金表面位点.
- 这些发现为通过控制原子级合金和晶格结构来设计高活性合金电催化剂提供了新的见解.
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