修改单原子Ni/CeO2表面电子和空间分布的机制以提高CO-SCR反应性:密度函数理论研究研究
Mingtao Yang1, Jiancheng Yang2, Long Chen2
1School of Chemical Engineering and Technology, Tianjin Key Laboratory of Clean Energy and Pollutant Control, Hebei University of Technology, Tianjin 300401, China.
Langmuir : the ACS journal of surfaces and colloids
|February 21, 2025
概括
通过表面生成策略开发单原子催化剂可以提高低温CO-SCR反应活性和N2选择性. 这种异质催化剂的原子级调制对于有效的NO和CO去除至关重要.
科学领域:
- 不同质的催化剂.
- 表面科学是一门科学.
- 计算化学是一种计算化学.
背景情况:
- 低温CO-SCR (一氧化碳选择性催化降解) 反应需要提高活性和N2选择性.
- 异质催化剂的原子级调制是一种有希望的,但在实验上具有挑战性的策略.
- 了解原子级反应机制对于催化剂设计至关重要.
研究的目的:
- 开发一个单原子载荷的表面生成策略,用于构建单原子催化剂.
- 为了研究Ni吸附对CeO2 (1 1 1) 表面上CO-SCR反应的影响.
- 为设计用于协同消除NO和CO的新型催化剂提供理论指导.
主要方法:
- 密度功能理论 (DFT) 分析.密度功能理论 (DFT) 分析.
- 电子结构分析.
- 过渡状态理论 (TST) 的计算.
- 热力学和动力学分析.
主要成果:
- 吸附显著降低了N2生成的能量屏障 (1.864 eV),并增加了CeO2 (1 1 1) 上N2O生成的屏障 (1.498 eV).
- 通过O原子填充空位的Ni促进N2形成的途径在热力学上是自发的,在动力学上是有利的.
- 孤立的Ni原子诱导电子合和再分配,激活CeO2表面的邻近氧气位点.
结论:
- 单原子载荷表面生成策略有效地提高了低温CO-SCR活性和N2选择性.
- 对CeO2的修饰起到促进作用,抑制N2O的形成,有利于N2的产生.
- 这项研究为设计用于环境修复的先进催化剂提供了机械学理解和理论基础.
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