反应驱动的表面重组和选择性控制在醇催化有氧氧化过程中超过Pd
Adam F Lee1, Christine V Ellis, James N Naughton
1Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK. leeaf@cardiff.ac.uk
Journal of the American Chemical Society
|March 29, 2011
概括
纳米颗粒 (Pd) 催化剂有助于克罗醇的选择性有氧氧化. 表面氧化物是活性相,有动态的氧化还原过程控制反应通路.
科学领域:
- 不同质的催化剂.
- 表面科学是一门科学.
- 无机化学 无机化学 无机化学
背景情况:
- 选择性有氧氧化对于合成有价值的化学品至关重要.
- 基于的催化剂被广泛使用,但它们的活性阶段和机制需要进一步阐明.
- 了解反应动态是优化催化剂性能的关键.
研究的目的:
- 为了确定在Pd纳米颗粒上的基醇在蒸汽相选择性有氧氧化过程中的催化活性相.
- 在反应条件下阐明的动态氧化还原过程.
- 了解这些过程如何控制对所需产品的选择性,而不是完全燃烧.
主要方法:
- 采用了同步,时间解析的扩散反射红外里埃变换光谱 (DRIFTS),质谱 (MS) 和X射线吸收光谱 (XAS).
- 在现场研究是在反应条件下的循环实验期间进行的.
- 使用纳米颗粒催化剂.
主要成果:
- 表面氧化物被确定为选择性有氧氧化过程中的催化活性相.
- 观察到动态的,反应诱导的氧化还原过程.
- 发现这些氧化还原动力学直接影响了选择性氧化和完全燃烧途径之间的控制.
结论:
- 克罗醇对纳米颗粒Pd的选择性有氧氧化过程中的活性阶段是表面氧化物.
- 氧化还原循环是决定反应选择性的关键因素.
- 这种机理性的洞察力为设计用于选择性氧化反应的改进的催化剂提供了基础.
相关概念视频
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