Andersson Linnéa, Sprik Michiel, Hutter Jürg, Zhang Chao
Department of Chemistry-Ångström Laboratory, Uppsala University, Lägerhyddsvägen 1, BOX 538, 75121, Uppsala.
Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge, CB2 1EW, United Kingdom.
Angew Chem Int Ed Engl. 2025 Jan 2;64(1):e202413614. doi: 10.1002/anie.202413614. Epub 2024 Nov 4.
We have studied polarized Au(100) and Au(111) electrodes immersed in electrolyte solution by implementing finite-field methods in density functional theory-based molecular dynamics simulations. This allows us to directly compute the Helmholtz capacitance of electric double layer by including both electronic and ionic degrees of freedom, and the results turn out to be in excellent agreement with experiments. It is found that the electronic response of Au electrode makes a crucial contribution to the high Helmholtz capacitance and the instantaneous adsorption of Cl can lead to a charge inversion on the anodic polarized Au(100) surface. These findings point out ways to improve popular semi-classical models for simulating electrified solid-liquid interfaces and to identify the nature of surface charges therein which are difficult to access in experiments.
我们通过在基于密度泛函理论的分子动力学模拟中采用有限场方法，研究了浸入电解质溶液中的极化金（100）和金（111）电极。这使我们能够通过同时包含电子和离子自由度直接计算双电层的亥姆霍兹电容，结果与实验结果非常吻合。研究发现，金电极的电子响应对高亥姆霍兹电容起着关键作用，并且Cl的瞬时吸附会导致阳极极化的金（100）表面发生电荷反转。这些发现指出了改进用于模拟带电固液界面的流行半经典模型的方法，并确定了其中难以通过实验获取的表面电荷的性质。
