双相 Pd-Au 合金催化剂用于低温 CO 氧化
1State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China.
Journal of the American Chemical Society
|July 29, 2010
概括
金纳米合金催化剂显示出最佳的低温CO氧化活性和稳定性. 双相分离为富含Pd和富含Au的组件可提高催化应用的耐用性.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术纳米技术
背景情况:
- 低温一氧化碳 (CO) 氧化对于各种催化应用至关重要.
- (Pd) 和金 (Au) 是催化中的关键金属,但它们的合金性能各不相同.
- 了解纳米合金结构-活性关系对于催化剂设计至关重要.
研究的目的:
- 为了研究金 (Pd-Au) 纳米合金催化剂的低温CO氧化性能,这些催化剂支着二氧化烟.
- 为了将催化剂的组成,结构和表面特性与催化活性和稳定性相关联.
- 探索双相Pd-Au纳米合金作为催化中的耐用替代品的潜力.
主要方法:
- 在二氧化烟雾上合成Pd-Au纳米合金组成系列.
- 使用X射线衍射 (XRD),X射线光电子谱学 (XPS) 和高分辨率传输电子显微镜 (HRTEM) 的表征.
- 在CO氧化过程中使用in situ Fourier转换红外光谱 (FTIR) 来研究表面物种.
主要成果:
- Pd-Au纳米合金表现出二相分离到富含Pd和富含Au的组件,除了纯金属.
- 对于Pd(4) Au(1) 组成,即Pd-丰富和Au-丰富相的混合物,观察到300K的最佳活性和稳定性.
- 表面分析显示了Pd丰富合金上的黄金缩,现场FTIR显示了Pd含量增加的Pd含量增加的Pd含量.
结论:
- 与纯 Au 催化剂相比,双相 Pd-Au 纳米合金在低温 CO 氧化中表现出优越的性能和稳定性.
- 观察到的黄金丰富和表面位点阻塞在富含Pd的合金中,有助于提高耐用性.
- 含金双相Pd纳米合金为各种催化反应提供了有希望的,高度耐用的替代品.
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