Related Experiment Video
Updated: Mar 20, 2026
20:38
AC Electrokinetic Phenomena Generated by Microelectrode Structures
Published on: July 28, 2008
12.0K
Theory of reactions at electrified interfaces
1Institute of Engineering Thermodynamics, Computational Electrochemistry, German Aerospace Center (DLR), 70569 Stuttgart, Germany. jessica.lueck@dlr.de arnulf.latz@dlr.de.
Physical Chemistry Chemical Physics : PCCP
|May 25, 2016
Summary
A new theory explains charge and electron transfer at interfaces in electrochemical systems like batteries. It reveals how double-layer charging drives intercalation reactions in lithium-ion batteries.
Area of Science:
- Electrochemistry
- Materials Science
- Chemical Engineering
Background:
- Interfacial processes critically influence electrochemical system performance.
- Current models lack depth, relying on phenomenological descriptions of charged interfaces.
Purpose of the Study:
- To present a universal theory for charge and electron transfer at charged interfaces.
- To apply this theory to the electrochemical double layer in solid-electrode/liquid-electrolyte systems.
- To model intercalation reactions in lithium-ion batteries.
Main Methods:
- Development of a generic theoretical framework for interfacial reactions.
- Application of the theory to the electrochemical double layer model.
- Analysis of the intercalation reaction as a two-step process (desolvation/adsorption and insertion).
Main Results:
- The theory provides deeper insights into interfacial phenomena beyond phenomenological models.
- The intercalation reaction in lithium-ion batteries is modeled as a sequential desolvation, adsorption, and insertion process.
- Double-layer charging is identified as the essential driving force for interfacial charge transfer.
Conclusions:
- The presented generic theory offers a more profound understanding of electrochemical interfacial reactions.
- This model enhances the description of processes in systems like lithium-ion batteries.
- The findings highlight the crucial role of the electrochemical double layer in facilitating charge transfer.
Related Concept Videos
01:30Processes at Electrodes
45
The electrode interacts with ions in the electrolyte solution at its interface. The rate of oxidation and reduction depends on the speed at which electrons can transfer through this interface. As ions attach to or leave the electrode surface, the electrode acquires a charge, and an electrical potential forms across the interface, making the process more difficult to reach equilibrium. The charge on the electrode affects the local ion concentrations in the solution, though thermal motion...
45
01:30The Electrical Double Layer
114
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...
114
01:24Electrochemical Systems
57
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution,...
57
01:23Theory of Strong Electrolytes
55
The interionic forces of the strong electrolytes depend on the solvent's dielectric constant, which is the ability of a solvent to store electrical energy, based on its polarizability. and the solution's concentration. In high-dielectric solvents and in dilute solutions, weak electrostatic forces keep ions apart. However, in low-dielectric solvents or concentrated solutions, stronger interionic forces may cause ions to pair up as ionic doublets despite being fully ionized. The theory of strong...
55
01:06Interfacial Electrochemical Methods: Overview
1.0K
Interfacial electrochemical methods focus on the phenomena occurring at the boundary between an electrode and a solution, as opposed to bulk methods that concentrate on the solution's overall properties. These interfacial methods are classified as either static or dynamic based on the presence of a nonzero current in the electrochemical cell and the consistency of analyte concentrations. Static methods, such as potentiometry, measure the cell's potential without any significant current...
1.0K
03:00Electrolysis
31.5K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
31.5K