Modeling stepped Pt/water interfaces at potential of zero charge with ab initio molecular dynamics
Modeling stepped Pt/water interfaces at potential of zero charge with ab initio molecular dynamics
复制标题
用从头算分子动力学模拟零电荷势下的阶梯式 Pt/水界面
DOI：
10.1063/5.0100678
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Jun Cheng
中科院分区：
文献类型：
--
作者：
Ao Chen;Jia-Bo Le;Yongbo Kuang;Jun Cheng
阶梯状金属/水界面的零电荷电位和结构是一个值得深入研究的问题，因为对于许多电催化反应，阶梯状表面比原子级平坦表面具有更高的活性。在这里，一系列的阶梯Pt/水界面模拟在不同的步骤密度从头计算分子动力学。结果发现，Pt/水界面的结构显着影响的台阶密度，特别是在化学吸附水的分布方面。金属表面的台阶位置比平台位置更适合于水的化学吸附，并且直到台阶密度非常低，水将化学吸附在平台上。此外，研究还发现，阶梯状Pt/水界面的PZC通常小于Pt（111）界面，这种差异主要归因于两者功函数的不同，从而为估算阶梯状金属表面的PZC提供了一种简单的方法.最后，有趣的是看到，伏特电位差几乎是相同的Pt/水界面与不同的步骤密度，虽然他们的界面结构和电荷转移的幅度明显不同。
It is worth understanding the potentials of zero charge (PZCs) and structures of stepped metal/water interfaces, because for many electrocatalytic reactions, stepped surfaces are more active than atomically flat surfaces. Herein, a series of stepped Pt/water interfaces are modeled at different step densities with ab initio molecular dynamics. It is found that the structures of Pt/water interfaces are significantly influenced by the step density, particularly in regard to the distribution of chemisorbed water. The step sites of metal surfaces are more preferred for water chemisorption than terrace sites, and until the step density is very low, water will chemisorb on the terrace. In addition, it is revealed that the PZCs of stepped Pt/water interfaces are generally smaller than that of Pt(111), and the difference is mainly attributed to the difference in their work function, providing a simple way to estimate the PZCs of stepped metal surfaces. Finally, it is interesting to see that the Volta potential difference is almost the same for Pt/water interfaces with different step densities, although their interface structures and magnitude of charge transfer clearly differ.