arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2212.08855physics.chem-phcond-mat.mtrl-sci
收藏

水在Pd(111)表面解离的从头算研究

Ab initio study of water dissociation on a charged Pd(111) surface

Karen Fidanyan, Guoyuan Liu, Mariana Rossi

摘要:

分子和电极表面之间的相互作用在电化学过程中起着关键作用,并且是实验和理论上广泛研究的主题。在这篇手稿中,我们解决了水的解离反应的Pd(111)电极表面,模拟为嵌入在外部电场的平板。我们的目标是解开表面电荷和零点能之间的关系,在帮助或阻碍这一反应。我们用色散校正的密度泛函理论和一种有效的平行实现的轻推弹性带方法计算了能垒。我们发现,最低的解离势垒,因此最高的反应速率,发生在外地达到的强度,其中两个不同的几何形状的水分子在反应物状态是同样稳定的。另一方面,尽管反应物状态发生了显著变化,但零点能对该反应的贡献在宽范围的电场强度内几乎保持恒定。有趣的是,我们表明,应用电场,诱导表面上的负电荷可以使核隧穿更显着的这些反应。

英文摘要:

Interactions between molecules and electrode surfaces play a key role in electrochemical processes and are a subject of extensive research, both experimental and theoretical. In this manuscript, we address the water dissociation reaction on a Pd(111) electrode surface, modelled as a slab embedded in an external electric field. We aim at unraveling the relationship between surface charge and zero-point-energy in aiding or hindering this reaction. We calculate energy barriers with dispersion-corrected density-functional theory and an efficient parallel implementation of the nudged-elastic-band method. We show that the lowest dissociation barrier, and consequently highest reaction rate, takes place when the field reaches a strength where two different geometries of the water molecule in the reactant state are equally stable. Zero-point energy contributions to this reaction, on the other hand, remain nearly constant across a wide range of electric field strengths, despite significant changes in the reactant state. Interestingly, we show that the application of electric fields that induce a negative charge on the surface can make nuclear tunneling more significant for these reactions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑