Related Experiment Video
Updated: Jan 7, 2026
09:58
A Modular Microfluidic Technology for Systematic Studies of Colloidal Semiconductor Nanocrystals
Published on: May 10, 2018
10.0K
Architected Redox-Active Colloids for Tunable Charge Transport in Aqueous Systems
Sinae Lee1, Jeongwon Kim2, Eunsung Kim1,3
1Department of Chemical Engineering and Materials Science, Ewha Womans University, Seoul, Republic of Korea.
Small (Weinheim an Der Bergstrasse, Germany)
|December 29, 2025
Summary
Architected redox-active colloids (RACs) with organized ethyl viologen (EV) domains enhance electrochemical performance in aqueous systems. Internal colloid architecture, not just content, dictates charge transport and stability for sustainable energy applications.
Area of Science:
- Soft matter physics
- Materials science
- Electrochemistry
Background:
- Colloids are foundational soft matter, traditionally passive but increasingly explored for programmable electrochemical functions.
- Aqueous electrolytes face limitations like narrow potential windows and poor redox site stability, hindering sustainable redox systems.
- Existing colloidal dispersions offer limited control over electrochemical properties.
Purpose of the Study:
- To address limitations in aqueous electrolytes by developing architected redox-active colloids (RACs).
- To investigate the impact of internal colloid architecture on electrochemical performance.
- To establish a generalizable strategy for designing soft colloidal materials with integrated charge transport.
Main Methods:
- Fabrication of RACs using polystyrene (PS) spheres embedded with ethyl viologen (EV) via a swelling-mediated loading process.
- Independent control over particle size, redox-site density, and internal EV organization.
- Electrochemical characterization to assess redox capacity, reversibility, charge transport, and stability.
Main Results:
- RACs allow independent control over particle size, redox-site density, and internal EV organization, enabling direct control over redox capacity and reversibility.
- Colloids with densely organized and spatially continuous EV domains exhibited enhanced charge transport and stability.
- Internal architecture, rather than total redox content, was found to govern electrochemical performance.
Conclusions:
- Architected redox-active colloids (RACs) provide a robust and flow-compatible platform for aqueous electrochemical systems.
- The internal architecture of colloids is critical for optimizing electrochemical performance, surpassing simple redox content.
- This work presents a generalizable strategy for designing soft colloidal materials with integrated charge transport functionality for sustainable energy applications.
Related Concept Videos
01:24Redox Reactions
58.1K
Oxidation-reduction or redox reactions involve the transfer of electrons from one molecule or atom to another. When an atom gains an electron, another atom must lose an electron, meaning oxidation and reduction must occur together. Since the redox occurs in pairs, the atom that gets oxidized is also called the reducing agent or reductant, and the atom that is reduced is also called the oxidizing agent or oxidant. A straightforward way to remember the definitions of oxidation and reduction is...
58.1K
01:27Redox Reactions
832
Redox reactions are vital biochemical processes that underpin energy metabolism in cells. These reactions involve the transfer of electrons between molecules, occurring in tandem as oxidation and reduction. Oxidation refers to the loss of electrons, while reduction denotes their gain. This coupling ensures the seamless flow of electrons through metabolic pathways. For example, in bacterial metabolism, glucose undergoes oxidation to carbon dioxide, while oxygen is simultaneously reduced to...
832
01:06Coagulation
1.2K
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
1.2K
02:58Balancing Redox Equations
61.3K
Electrochemistry is the science involved in the interconversion of electrical and chemical reactions. Such reactions are called reduction-oxidation, or redox reactions. These important reactions are defined by changes in oxidation states for one or more reactant elements and include a subset of reactions involving the transfer of electrons between reactant species. Electrochemistry as a field has evolved to yield sufficient insights on the fundamental principles of redox chemistry and multiple...
61.3K
01:09Colloidal precipitates
4.7K
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
4.7K
01:23Redox Equilibria: Overview
1.5K
A reduction-oxidation reaction is commonly called a redox reaction. In a redox reaction, electrons are transferred from one species to another rather than being shared between or among atoms. The reducing agent or reductant is the species that loses electrons and gets oxidized in the process. The species that gains electrons and gets reduced in the process is the oxidizing agent or oxidant. Redox reactions are represented as two separate equations called half-reactions, where one equation...
1.5K