在Ag-PdO的模型表面上的激活{101}
1Department of Nanotechnology and Nanomedicine, Graduate School of Natural Sciences, Hacettepe University, Ankara, Turkiye.
Turkish journal of chemistry
|November 13, 2025
概括
在氧化物 (PdO) 催化剂中加入银,降低了氧化过程的温度. 这在白银-PdO接口上创建了新的活性位点,促进了用于选择性催化剂的C-H键激活.
科学领域:
- 催化剂是一种催化剂.
- 表面科学是一门学科.
- 材料化学 材料化学
背景情况:
- 由于高的C-H键激活能量和完全氧化的有利性,烯氧化具有挑战性.
- 氧化物 (PdO),特别是 (101) 面,显示出高反应性,归因于不和的Pd和O原子.
研究的目的:
- 研究银 (Ag) 加入对氧化对PdO的影响.
- 了解新活性位点的形成及其对反应能量和选择性的影响.
主要方法:
- 在受控条件下利用温度编程反应光谱 (TPRS).
- 采用红头法来估计激活能量.
- 进行了二氧化碳脱落和Ag覆盖的定量分析.
主要成果:
- 普里斯PdO(101) 在~475K时显示出完全的氧化.
- 加入Ag引入了在~330K的新CO2脱吸峰值,表明了低温活动.
- 在Ag-PdO接口的C-H键激活能量减少了46kJ/mol.
- 低温活动与Ag覆盖率相关,但整体CO2产量下降.
结论:
- 银的结合改变了PdO101) 的能量,为氧化产生了活跃的接口部位.
- 双金属Ag-PdO催化剂为设计选择性部分氧化反应提供了潜力.
- 这项研究展示了一种通过加入不太反应性的金属来调整催化剂活性的策略.
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