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Updated: Jun 8, 2026

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.
Abstract:
The wettability of a titania surface, partially covered with octadecyltrihydrosilane, has been investigated as a function of solution pH. The results show that surface charge affects both static wettability and wetting kinetics. The static contact angle decreases above and below the point of zero charge of the titania surface in a Lippman-like manner as the pH is altered. The dependence of dynamic contact angle on velocity is also affected by pH. The molecular-kinetic theory (MKT) is used to interpret the dynamic contact angle data. The frequency of molecular displacement κ(0) strongly varies with surface charge, whereas the mean molecular displacement length λ is essentially unaffected. There is an exponential dependence of contact-line friction upon work of adhesion, which is varied simply by altering the pH.
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