Park Chanbum, Ghosh Soumya, Forbert Harald, Marx Dominik
Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany.
Tata Institute of Fundamental Research Hyderabad, Hyderabad, 500046, Telangana, India.
Nat Commun. 2025 Sep 19;16(1):8325. doi: 10.1038/s41467-025-63832-1.
Understanding the solvation structures of OH and HO at metal interfaces is crucial for developing efficient electrochemical devices. In this paper, we present a detailed investigation of the solvation structures of OH and HO near gold electrodes under alkaline and acidic aqueous conditions, using ab initio molecular dynamics simulations at controlled surface charge density conditions. Our findings reveal that the adsorption tendencies of OH and HO are strongly influenced by the oscillating net atomic charge of water normal to the electrified interface in concert with the distinct solvation patterns of these charge defects. While OH preferentially adsorbs onto the gold surface within the first water layer, the positive net atomic charge restricts the closest approach of HO to beyond the first water layer. We unveil resting and active states that support charge transfer processes at the gold/water interface, which critically involve Au atoms in a unique Grotthuss-like mechanism.
了解金属界面处OH和HO的溶剂化结构对于开发高效的电化学装置至关重要。在本文中，我们使用在可控表面电荷密度条件下的从头算分子动力学模拟，对碱性和酸性水溶液条件下金电极附近OH和HO的溶剂化结构进行了详细研究。我们的研究结果表明，OH和HO的吸附倾向受到垂直于带电界面的水的振荡净原子电荷的强烈影响，同时这些电荷缺陷具有独特的溶剂化模式。虽然OH优先吸附在第一水层内的金表面上，但正净原子电荷将HO的最接近距离限制在第一水层之外。我们揭示了支持金/水界面电荷转移过程的静止和活跃状态，这在一种独特的类Grotthuss机制中关键地涉及金原子。
