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Updated: Sep 22, 2025
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Dispersion of Nanomaterials in Aqueous Media: Towards Protocol Optimization
Published on: December 25, 2017
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Versatile strategy for homogeneous drying patterns of dispersed particles.
Marcel Rey1,2,3, Johannes Walter1,2, Johannes Harrer1,2
1Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany.
Nature Communications
|May 23, 2022
Summary
Researchers developed a new method to prevent the coffee ring effect, enabling uniform particle deposition. This strategy uses surface-modified particle dispersions to control drying patterns in technological applications.
Area of Science:
- Materials Science
- Fluid Dynamics
- Colloid Science
Background:
- The coffee ring effect, a common phenomenon, results in non-uniform particle deposition from drying droplets.
- This effect poses a significant challenge in industrial applications like inkjet printing and coating technologies.
- Achieving uniform particle distribution is crucial for the performance and quality of various manufactured products.
Purpose of the Study:
- To present a novel and adaptable strategy for creating homogeneous drying patterns.
- To overcome the limitations imposed by the coffee ring effect in particle deposition.
- To enable uniform particle deposition for technological processes.
Main Methods:
- Utilizing surface-modified particle dispersions with high-molecular weight surface-active polymers.
- Employing polymers that physisorb onto particle surfaces to provide steric stabilization.
- Leveraging enhanced particle adsorption to the air/liquid interface, inducing a thermal Marangoni backflow.
Main Results:
- Demonstrated prevention of particle accumulation and pinning at the droplet edge.
- Achieved uniform particle deposition patterns after drying, effectively eliminating the coffee ring effect.
- Showcased the method's independence from particle shape and applicability to diverse dispersion media.
Conclusions:
- Surface modification of particles offers a simple yet effective solution for uniform drying patterns.
- The developed strategy is practical for various industrial applications, including pigment particle processing.
- This approach enhances steric stabilization and controls particle behavior at the air/liquid interface for homogeneous deposition.
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