通过CO激活对原子分散的Pt/CeO2催化剂进行增强的催化氧化反应
Zihao Li1, Zhisong Liu1, Guanqun Gao1
1School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Environmental science & technology
|June 27, 2024
概括
CO激活显著提高了Pt/CeO2催化剂的低温一氧化碳 (CO) 氧化性能. 这种CO激活催化剂为汽车废气处理提供了更高的CO消耗率和稳定性.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 环境化学环境化学
背景情况:
- 汽车废气中一氧化碳 (CO) 的低温氧化对于环境保护至关重要.
- 现有的Pt/CeO2催化剂在实现高活性和稳定性方面面临挑战,特别是在较低的温度下.
- 以前的减少策略主要使用H2,忽视了CO本身作为减少剂的潜力.
研究的目的:
- 研究CO激活对原子分散Pt/CeO2催化剂低温氧化活性的影响.
- 为了比较CO激活Pt/CeO2与H2激活催化剂的性能.
- 阐明负责增强催化活性的潜在机制.
主要方法:
- 制造原子分散的Pt/CeO2.2. 这种材料的制造.
- 使用一氧化碳 (CO) 激活催化剂.
- 使用分析活性部位,表面特性和在模拟排气条件下的稳定性技术进行表征.
主要成果:
- 通过CO激活,90%的CO转化温度 (T90) 降低了256°C.
- 与未激活的催化剂相比,在200°C时实现了CO消耗率的20倍增加.
- CO激活产生了 Pt0 露台和表面氧气空缺 (Vo),增强了氧气的储存和激活.
- H2激活导致不活跃的PtOx形成,与CO激活不同.
结论:
- CO激活是提高Pt/CeO2催化剂低温CO氧化活性的一种高度有效的策略.
- 激活催化剂在处理汽车废气 (CO,C3H6,NH3) 方面表现出色的性能和稳定性.
- 了解二氧化碳激活的作用为设计有效的排放控制催化剂提供了新的途径.
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