在CeO2-Cu2O催化剂上氧化甲的水促进界面路径
Zongyuan Liu1, Erwei Huang2, Ivan Orozco2
1Chemistry Division, Brookhaven National Laboratory, Upton, NY 11973, USA.
概括
将水添加到氧化/氧化铜/铜催化剂中,可以加强对甲的选择性氧化. 这种催化过程涉及水分离和基物种的形成,改善甲醇产量和气相位移.
科学领域:
- 催化剂
- 表面化学
- 氧化反应
背景情况:
- 在催化过程中,选择性氧化甲为甲醇是一个重大挑战.
- 现有的催化剂通常会产生不良的副产品,如一氧化碳和二氧化碳.
研究的目的:
- 研究水在促进甲选择性氧化成甲醇中的作用.
- 阐明水如何影响CeO2/Cu2O/Cu111系统上的催化剂选择性.
主要方法:
- 使用环境压力X射线光电子光谱 (AP-XPS) 来分析表面物种.
- 使用密度函数理论 (DFT) 计算来建模反应路径.
- 进行动力蒙特卡洛 (KMC) 模拟以了解反应动力学.
主要成果:
- 在催化剂上添加水的甲和氧气导致了表面甲氧基的形成.
- 在水的存在下,AP-XPS证实了加速的甲醇生产.
- DFT和KMC模拟显示了CeO2-Cu2O/Cu111接口的优先水分离.
结论:
- 从水中提取的吸附基物种在增强甲醇选择性方面起着至关重要的作用.
- 通过阻断O-O键裂变来抑制一氧化碳和二氧化碳的形成.
- 水有助于中间体转化为甲醇,并有助于产品的脱落.
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