为什么 (1 0 0) 露台断裂并产生键:二甲基乙烯在单晶电极上的氧化
Hongjiao Li1, Federico Calle-Vallejo, Manuel J Kolb
1Leiden Institute of Chemistry, Leiden University , P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Journal of the American Chemical Society
|August 29, 2013
概括
在表面的电催化有利于 (100) 梯田二甲基乙烯 (DME) 氧化. 这种偏好源于CO结合破解步骤,该步骤在步骤位点受到阻碍,影响了整体反应活性.
科学领域:
- 表面科学是一门科学.
- 电触媒溶解是一种电触媒.
- 计算化学是一种计算化学.
背景情况:
- 许多电催化反应显示出对面中心立方体 (fcc) 金属上的 (100) 梯田的偏好.
- 了解这种表面结构偏好对于设计高效的电催化剂至关重要.
研究的目的:
- 在上对二甲基乙烯 (DME) 的电化学氧化中研究表面结构偏好.
- 为了识别和澄清这种反应中基本的C-O结合破解步骤.
主要方法:
- 在各种表面上进行的联合单晶实验 (Pt(100),Pt(510),Pt(1010).
- 密度函数理论 (DFT) 计算以建模反应机制和吸附能.
- 分析表面结构灵敏度及其与反应活性的相关性.
主要成果:
- 确定C-O断层环节是表面结构灵敏性的关键因素.
- 这种破解联系的步骤在步骤站点上是不利的,但在Pt(100) 露台上是有效的.
- 一种CHOC吸附物被确定为前体,首选结合到Pt100) 露台上的特定位置.
结论:
- 对于DME氧化的电催化活性受到步骤位点密度的显著影响.
- 基于实验和计算发现,提出了DME电氧化的新机制.
- 建议使用一种一般公式来预测有利于 (100) 梯田的表面上的电催化活性.
相关概念视频
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