控制黄金表面的界面结:有机共溶剂的影响
Ziareena A Al-Mualem1, Keegan A Lorenz-Ochoa1, Lei Pan1
1Department of Chemistry, University of Texas at Austin, 105 E 24th St. A5300, Austin, Texas 78712, United States.
The journal of physical chemistry letters
|April 15, 2024
概括
二甲基硫氧化物 (DMSO) 辅溶剂改变了黄金表面的接口水网络. 这种重组,与DMSO丰富和水聚类,抑制质子扩散,阻碍电催化反应,如进化.
科学领域:
- 表面化学 表面化学
- 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:
- 水在电催化中至关重要,作为反应剂和溶剂.
- 接口水网对反应动力学和传输有重大影响.
- 像二甲基硫氧化物 (DMSO) 这样的辅溶剂可以修改这些网络以调整反应性.
研究的目的:
- 研究水-DMSO混合物对黄金表面界面结 (H-bonding) 网络的影响.
- 了解DMSO如何影响当地的环境和水结构在电极-电解质接口.
- 确定这些变化对电催化过程的影响,特别是进化反应.
主要方法:
- 表面增强的红外吸收光谱 (SEIRAS) 来探测接口物种和H键.
- 分子动力学 (MD) 模拟用于模拟水-DMSO混合物的界面结构和动力学.
- 结合实验和计算方法来分析接口属性.
主要成果:
- 黄金表面最好用脱水的DMSO分子进行丰富.
- 水-DMSO混合物呈现相位分离,在接口上形成明显的水集群.
- 模拟显示了表面受约束的"曲"水形状,限制了H-结合.
- 小水集群和不利的H键形状抑制了大量水的相互作用.
结论:
- 添加DMSO和随后的相分离创建了一个独特的接口环境.
- 受到限制的水集群和有限的H键抑制了质子扩散.
- 这种抑制质子扩散可以显著抑制电催化演化反应的效率.
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