Related Experiment Video
Updated: Jan 26, 2026
06:40
Biofunctionalization of Magnetic Nanomaterials
Published on: July 16, 2020
3.0K
Versatile electrification of two-dimensional nanomaterials in water
Benoît Grosjean1, Marie-Laure Bocquet2, Rodolphe Vuilleumier3
1PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 24 Rue Lhomond, 75005, Paris, France.
Nature Communications
|April 12, 2019
Summary
Graphene and hexagonal boron nitride (h-BN) nanomaterials exhibit distinct water and ion transport behaviors. Hydroxide adsorption causes surface charging via different mechanisms, impacting ionic conductivity.
Area of Science:
- Nanofluidics and Surface Science
- Materials Science and Engineering
Background:
- Graphene and hexagonal boron nitride (h-BN) are key nanomaterials for nanofluidics.
- Experimental studies show contrasting electrification of water/graphene and water/h-BN interfaces.
- Understanding ion transport mechanisms at these interfaces is crucial.
Purpose of the Study:
- To investigate the mechanisms of hydroxide (OH-) ion adsorption and transport near graphene and h-BN surfaces.
- To elucidate the origins of the observed contrasting interfacial electrification.
- To develop a model explaining ionic surface conductivity.
Main Methods:
- Ab initio molecular dynamics simulations were employed to calculate free energies.
- Simulations focused on hydroxide ions in water interacting with graphene and h-BN layers.
- An analytic transport model was developed based on simulation findings.
Main Results:
- Both graphene and h-BN surfaces become charged due to hydroxide adsorption.
- Hydroxide exhibits weak physisorption on graphene and strong chemisorption on h-BN.
- Fast lateral dynamics and interfacial mobility of hydroxide were observed on graphene.
Conclusions:
- Distinct adsorption mechanisms on graphene and h-BN explain the observed interfacial electrification.
- The rapid ion dynamics on graphene contribute to significant ionic surface conductivity.
- The developed transport model quantitatively reproduces experimental data.
Related Concept Videos
01:23States of Water
56.5K
Water exists in any one of the three classical states: solid (ice), liquid (water), and gas (steam or water vapor). The state of water depends on i) the intermolecular forces that draw molecules together and ii) the kinetic energy that leads to movements that pull them apart.
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
56.5K
03:40Dimensional Analysis
60.9K
Dimensional analysis, also known as the factor label method, is a versatile approach for mathematical operations. The main principle behind this approach is: the units of quantities must be subjected to the same mathematical operations as their associated numbers. This method can be applied to computations ranging from simple unit conversions to more complex and multi-step calculations involving several different quantities and their units.
Conversion Factors and Dimensional Analysis
The unit...
Conversion Factors and Dimensional Analysis
The unit...
60.9K
02:34Water and Mineral Acquisition
35.5K
Specialized tissues in plant roots have evolved to capture water, minerals, and some ions from the soil. Roots exhibit a variety of branching patterns that facilitate this process. The outermost root cells have specialized structures called root hairs that increase the root surface, thus increasing soil contact. Water can passively cross into roots, as the concentration of water in the soil is higher than that of the root tissue. Minerals, in contrast, are actively transported into root cells.
35.5K
01:19Quality of Water
516
In concrete preparation, the quality of water is paramount as it affects the strength and durability of the concrete. Potable water is usually preferred; however, it must not have excessive sodium or potassium to prevent compromising the concrete's integrity. Water quality is typically evaluated based on impurities such as dissolved solids, chlorides, and sulfates, and its pH value is ideally between 6 and 8. Even slightly acidic natural water may be acceptable unless it contains harmful...
516
01:00The Water Cycle
28.2K
The Earth’s hydrosphere includes all of the areas where the storage and movement of water occurs. Since water is the basis of all living processes, the cycling of water is extremely important to ecosystem dynamics.
28.2K
01:22Effect of Sea Water on Concrete
1.0K
Concrete exposed to seawater can undergo degradation like the dissolution of ettringite and gypsum, increasing the material's porosity and decreasing its strength. In contrast, the crystallization of salts within the concrete's pores can cause expansion, particularly above the waterline where evaporation occurs. Nonetheless, this expansion only happens when seawater, enabled by the concrete's permeability, manages to infiltrate the structure.
Concrete in areas between tide marks,...
Concrete in areas between tide marks,...
1.0K