通过协同原子分散的CeV双位点实现广泛温度的NOx去除:激活速率决定的步骤
Pengxin Zeng1, Zijian Zhou1, Lei Liu1
1State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Hubei, Wuhan, 430074, China.
Journal of colloid and interface science
|September 3, 2025
概括
与商业催化剂相比,原子分散的Ce-V/TiO2催化剂在更广泛的温度范围内提供了更高的NOx去除效率. 这种进步提高了选择性催化还原的活性位点利用率和催化性能.
科学领域:
- 环境科学与工程
- 材料科学
- 催化剂
背景情况:
- 商用V-W/TiO2催化剂广泛用于煤电厂的氧化物排放控制.
- 现有的催化剂运行温度范围有限,活动场所利用率低,阻碍了氧化物去除效率,特别是在负载波动期间.
研究的目的:
- 使用双站点协调策略开发原子分散的Ce-V/TiO2催化剂.
- 增强主动站点的分散性,并解决速度决定步骤中的低转换频率 (TOF) 和高能耗障碍的限制.
- 在扩大工作温度范围内提高氧化物去除效率.
主要方法:
- 通过双站点协调策略合成原子分散的Ce-V/TiO2催化剂.
- 在相同条件下评估氧化物去除效率和现场活跃利用率.
- 密度功能理论 (DFT) 分析以调查反应机制和能量障碍.
主要成果:
- 在290°C到450°C之间,Ce-V/TiO2实现了90%的NOx转化,比商业催化剂 (365-425°C) 显著更广泛.
- Ce-V/TiO2的TOF为3.58×10^-3s^-1,是商业催化剂的1.52倍.
- DFT分析显示,Ce-V协同作用降低了NH3解离的激活能量,并减少了关键反应途径中的能量障碍.
结论:
- Ce-V/TiO2催化剂表现出优异的氧化物去除效率和更广泛的操作温度范围,由于增强了活性点分散和协同效应.
- Ce-V协同有效地降低了决定速度的步骤中的能量障碍,克服了低温活动的限制.
- 这项研究提出了一个有前途的策略,用于在不同温度条件下开发高效的选择性催化降解催化剂.
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