现场氧化研究Pt(110)及其与CO的相互作用
Derek R Butcher1, Michael E Grass, Zhenhua Zeng
1Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|November 11, 2011
概括
((110) 表面暴露于氧气形成表面氧化物类似于纳米颗粒的表面氧化物. 一氧化碳可以去除化学吸收的氧气和表面氧化物,为催化过程提供了洞察力.
科学领域:
- 表面科学是一门科学.
- 催化剂是一种催化剂.
- 材料科学是一种材料科学.
背景情况:
- (Pt) 催化剂在许多工业过程中至关重要.
- 了解Pt上的表面结构是优化催化活性的关键.
- 开放的Pt表面与Pt纳米粒子催化剂有相似之处.
研究的目的:
- 研究在O2暴露的Pt110上形成的结构.
- 确定这些结构与CO的稳定性和反应性.
- 将发现与Pt纳米粒子催化剂上的催化过程联系起来.
主要方法:
- 环境压力X射线光电子谱学 (AP-XPS).
- 高压扫描道显微镜 (HP-STM).
- 密度函数理论 (DFT) 的计算.
主要成果:
- 在低O2压力下,只能观察到化学吸收的氧气.
- 在0.5 Torr O(2) 时,多层的α-PtO(2) 样表面氧化物岛屿形成.
- 在270K的温度下,CO可以去除化学吸收的氧和表面氧化物.
结论:
- 在Pt(110) 上的表面氧化物结构类似于Pt纳米粒子上的结构.
- 碳化合物的反应性为开放的Pt表面的催化机制提供了洞察力.
- 在高压下对模型催化剂进行实地研究是有价值的.
相关概念视频
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