高活性和持久的基于Rh-Mo的催化剂用于NO-CO-C3H6-O2反应,通过使用混合集群来制备
Shun Hayashi1, Shinji Endo2, Hiroki Miura2,3,4
1Division of Physical Sciences, Department of Science and Engineering, National Museum of Nature and Science, Ibaraki 305-0005, Japan.
ACS materials Au
|December 13, 2023
概括
本研究引入了一种用于制备Rh-Mo催化剂的新型混合集群方法,通过创建密集的Rh/MoO接口点来增强NO-CO-C3H6-O2反应的活性和耐久性.
科学领域:
- 催化科学与技术 催化科学与技术
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 为汽车废气处理开发高效的催化剂至关重要.
- 传统方法通常会产生具有有限活性位点和耐久性的催化剂.
- 金属氧化物接口是催化活性的关键.
研究的目的:
- 利用混合集群开发一种新的催化剂制备方法.
- 用这种方法制备的Rh-Mo催化剂的催化性能进行研究.
- 了解这些催化剂的结构-活性-耐久性关系.
主要方法:
- 一个Rh-Mo混合集群前体的合成,[(RhCp*) 4Mo4O16].
- 通过混合集群制备Rh-Mo催化剂,并与共浸和原始Rh.进行比较.
- 在NO-CO-C3H6-O2反应中的催化活性评估和在1273K的热耐久性测试.
主要成果:
- 混合聚类显著增强了催化剂活性,与共浸和原始Rh.相比.
- 混合集群催化剂表现出极好的耐用性,可以抵抗高温老化.
- 高密度的Rh/MoO接口点被确定为性能改善的来源.
- 观察到一种独特的NO降解机制,涉及C3H6部分氧化和NCO中间体.
结论:
- 混合集群是一种有效的策略,用于创建高密度金属/氧化物界面活性站点.
- 开发的Rh-Mo催化剂在汽车废气处理方面表现出卓越的活性和耐用性.
- 独特的接口部位和反应机制有助于提高催化性能和稳定性.
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