Electrical Double Layers. Double Layers at Single‐crystal and Polycrystalline Electrodes

Abstract

The sections in this article are General Aspects The Potential of Zero Charge and Electric Double‐layer Structure Differential Capacitance of Electrode–Electrolyte Solution Interface Electrical Double‐layer Structure at Solid Electrodes Surface Roughness of Solid Electrodes The Applicability of the Gouy–Chapman–Stern–Grahame Model to Solid Electrodes Shape of C , E Curves Parsons and Zobel Plot Method Surface Roughness and Shape of Inner‐layer Capacitance Curves Polycrystalline Electrode Models Debye Length–dependent Surface Roughness Model Electric Double Layer and Fractal Structure of Surface Experimental Aspects. Short Review of Data Silver Gold Copper Lead Tin Zinc Cadmium Bismuth Antimony Iron Nickel Pt ‐group Metals General Correlations Zero‐charge Potential and Reticular Density of Planes Potential of Zero Charge, Work Function, Interfacial Parameter, and Inner‐layer Capacitance Data of Quantum‐chemical Calculations Adsorption of Organic Compounds and Hydrophilicity of Electrode

Effects of applied voltage on water at a gold electrode interface from ab initio molecular dynamics

“…In the absence of ions, we are satisfied to recover a reasonable differential capacitance for Au(111)/water towards the bottom of the measured range of C d . 67 Similar values of C d have been achieved for Au(111)/water with a fully implicit solvent with specifically tuned parameters 25 and with a monolayer of water. 33 Our results recover this macroscopic electrical property from short AIMD trajectories and an effectively fully explicit solvent.…”

Influence of the Nature of the Alkali Metal Cations on the Electrical Double-Layer Capacitance of Model Pt(111) and Au(111) Electrodes

“…Interestingly, the slopes for those two metal electrodes were almost identical (Figure A). As is also seen from Figures and , the Pt(111) electrodes demonstrated, in general, higher double-layer capacitances compared with Au(111) in all AM ClO 4 solutions, which, for example, might be in some cases explained by the differences in the work functions of the electrodes …”

“…The electrical double layer (EDL) is a structure that often determines the functionality of multiple important systems, − ranging from heterogeneous catalysts to colloids and from batteries to fuel cells and supercapacitors. − The structure of the double layer depends on the properties of electrodes and electrolyte composition. However, apart from very few examples, this connection remains largely qualitative for the overwhelming majority of systems.…”

“…One way to shed some light on these phenomena is to reveal the influence of the alkali metal cations on the EDL capacitance, C DL , of model electrocatalyst materials, as the EDL can be modeled as a capacitor. For metal electrodes, the EDL is assumed to consist of contributions originating from the so-called inner ( C i ) and the diffuse layer capacitance, where the former one is independent of the electrolyte. ,, In a simplistic equation, one can see that closer to the potential of zero charge, the C DL is roughly proportional to the relative permittivity (ε) of the solvent at the constant electrolyte concentration ( c ) (eq , details of this can be found in ref ). Because there is no direct experimental technique to accurately estimate the concentration of the ions at the outer Helmholtz layer, exploring the influence of the nature of the cations on C DL is perhaps one of the affordable ways to reveal changes in the double-layer properties with the electrolyte composition.…”

“…For metal electrodes, the EDL is assumed to consist of contributions originating from the so-called inner (C i ) and the diffuse layer capacitance, where the former one is independent of the electrolyte. 1,20,21 In a simplistic equation, one can see that closer to the potential of zero charge, the C DL is roughly proportional to the relative permittivity (ε) of the solvent at the constant electrolyte concentration (c) (eq 1, details of this can be found in ref 1).…”