Skip to Main content Skip to Navigation
Journal articles

Effect of the metallicity on the capacitance of gold–aqueous sodium chloride interfaces

Abstract : Electrochemistry experiments have established that the capacitance of electrode–electrolyte interfaces is much larger for good metals, such as gold and platinum, than for carbon-based materials. Despite the development of elaborate electrode interaction potentials, to date molecular dynamics simulations are not able to capture this effect. Here, we show that changing the width of the Gaussian charge distribution used to represent the atomic charges in gold is an effective way to tune its metallicity. Larger Gaussian widths lead to a capacitance of aqueous solutions (pure water and 1 M NaCl) in good agreement with recent ab initio molecular dynamics results. For pure water, the increase in the capacitance is not accompanied by structural changes, while in the presence of salt, the Na+ cations tend to adsorb significantly on the surface. For a strongly metallic gold electrode, these ions can even form inner sphere complexes on hollow sites of the surface.
Document type :
Journal articles
Complete list of metadata

https://hal.sorbonne-universite.fr/hal-03329773
Contributor : Gestionnaire Hal-Su Connect in order to contact the contributor
Submitted on : Tuesday, August 31, 2021 - 11:36:50 AM
Last modification on : Wednesday, November 17, 2021 - 12:32:46 PM

File

Serva et al. - 2021 - Effect o...
Files produced by the author(s)

Identifiers

Citation

Alessandra Serva, Laura Scalfi, Benjamin Rotenberg, Mathieu Salanne. Effect of the metallicity on the capacitance of gold–aqueous sodium chloride interfaces. Journal of Chemical Physics, American Institute of Physics, 2021, 155 (4), pp.044703. ⟨10.1063/5.0060316⟩. ⟨hal-03329773⟩

Share

Metrics

Record views

77

Files downloads

136