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Updated: Jun 8, 2026
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Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
Influence of surface charge on wetting kinetics
Lee San Puah1, Rossen Sedev, Daniel Fornasiero
1Ian Wark Research Institute, University of South Australia, Mawson Lakes Campus, Adelaide 5095, Australia.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 16, 2010
Summary
Surface charge significantly influences titania surface wettability and wetting dynamics. Altering solution pH changes the contact angle and molecular displacement frequency, impacting contact-line friction.
Area of Science:
- Surface Chemistry
- Materials Science
- Physical Chemistry
Background:
- Wettability is crucial for material surface interactions.
- Understanding how surface charge affects wettability is key for various applications.
- Titania surfaces are widely used, making their wettability characterization important.
Purpose of the Study:
- To investigate the wettability of a titania surface modified with octadecyltrihydrosilane.
- To determine the effect of solution pH on static and dynamic wettability.
- To analyze the relationship between surface charge, wetting kinetics, and molecular interactions.
Main Methods:
- Surface modification of titania with octadecyltrihydrosilane.
- Contact angle measurements (static and dynamic) at varying pH.
- Application of the molecular-kinetic theory (MKT) to interpret dynamic contact angle data.
Main Results:
- Surface charge, controlled by pH, affects both static wettability and wetting kinetics.
- Static contact angle exhibits a Lippman-like decrease around the point of zero charge.
- Dynamic contact angle dependence on velocity is pH-sensitive; molecular displacement frequency varies with surface charge.
Conclusions:
- Solution pH is a critical factor controlling titania surface wettability and wetting dynamics.
- Surface charge modulates molecular displacement frequency, influencing contact-line friction through an exponential dependence on work of adhesion.
- Findings provide insights into controlling surface interactions via pH manipulation.
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