在现场表面的Mn-Mn二次位点决定了CO化活性和C2对MnRh二次催化剂的选择性
Ke-Xiang Zhang1, Zhi-Pan Liu1,2
1Collaborative Innovation Center of Chemistry for Energy Material, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Key Laboratory of Computational Physical Science, Department of Chemistry, Fudan University, Shanghai 200433, China.
Journal of the American Chemical Society
|September 19, 2024
概括
研究人员使用机器学习确定了从合成气中生产乙醇的活性部位. 在催化剂上的-二元位点显著增强C2氧化物形成,提高工业应用的效率和选择性.
科学领域:
- 催化剂
- 材料科学
- 计算化学
背景情况:
- 从合成气中生产乙醇对于可持续能源至关重要.
- 促进的 (MnRh) 催化剂显示出高C2氧化物选择性.
- 人们对MnRh催化剂的活性部位了解甚少.
研究的目的:
- 在反应条件下确定Rh表面上最稳定的Mn相.
- 阐明C2氧化物形成的活性部位的原子结构.
- 了解反应机制并优化乙醇生产.
主要方法:
- 大规模的机器学习全球优化,以探索 Rh 表面上的 Mn 结构.
- 基于机器学习的过渡状态探索,绘制反应网络.
- 微动力学模拟以确定反应速度和选择性.
主要成果:
- 主要在Rh上占据地下位置,并与氧化吸附物形成表面合金.
- 在单原子步边的Mn-Mn二次位点被确定为真正的活性位点.
- Mn-Mn二次位点的周转频率是纯Rh位点的10^7倍,在523K时具有52%的C2选择性.
结论:
- Mn-Mn二次位点对于有效的C-O键裂变和C2中间体的化至关重要.
- 与纯Rh相比,这些地点显著提高了乙醇生产的选择性和速度.
- 这项研究澄清了活性部位,为改进合成气转化催化剂设计铺平了道路.
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