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在分子-金属界面的单原子兴奋剂:Rh如何影响表面爆炸动力学

Avery S Daniels¹, Andrew J Gellman², E Charles H Sykes¹

¹Department of Chemistry, Tufts University, Medford, Massachusetts 02155-5813, United States.

The journal of physical chemistry letters

|April 8, 2025

概括

将罗 (Rh) 原子添加到铜 (Cu) 表面会极大地改变酸 (TA) 的分解. Rh加速了启动和爆炸性分解,使得可以在较低的温度下控制这些表面反应.

科学领域:

表面化学和催化作用
化学动力学化学动力学
材料科学是一种材料科学.

背景情况:

控制界面反应对于大气,环境,生物化学,催化和腐蚀至关重要.
tartaric 酸 (TA) 在Cu ((100) 上的分解显示了自催化动力学,其开始缓慢,随后是快速的分解 ("表面爆炸").
这些反应对初始条件非常敏感,因此需要研究反应性原子的位置如何影响动力学.

研究的目的:

为了研究催化活性 (Rh) 原子对葡萄酸 (TA) 分解的表面反应动力学的影响.
了解Rh原子的位置 (在分子-金属接口上或以上) 如何影响Cu上的TA分解率和机制.

主要方法:

利用温度编程反应 (TPR) 实验研究TA在修改的Cu100) 表面上的分解.
在Rh嵌入 (TA/Rh/Cu) 和Rh-atop (Rh/TA/Cu) 表面与裸体Cu的TA分解的比较100).
采用异热TPR分析来确定启动和爆炸速度常数.

主要成果:

原子,无论是嵌入或放置在Cu100上的TA层之上,都显著降低了分解温度.
由于存在Rh,TA分解的启动 (k_init) 和爆炸 (k_exp) 速率常数都被增强了.
同热TPR分析证实了Rh在两个动力阶段的加速,在较低的温度下促进爆炸性分解.

结论:

TA的启动和爆炸性分解步骤都发生在金属分子界面.
在接口处的存在加快了这些接口反应.
少量反应性元素可以有效地控制表面的非线性运动过程.

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