Microscopic liquid–gas interface effect on liquid wetting

Jinming Zhang, Wei Ding, Zuankai Wang, Hao Wang, Uwe Hampel

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

Hypothesis: Young contact angle is widely applied to evaluate liquid wetting phenomena on solid surfaces. For example, it gives a truncated-spherical shape prediction of a droplet profile through the Young-Laplace equation. However, recent measurements have shown deviations between microscopic droplet profiles and the spherical shape, indicating that the conventional Young contact angle is insufficient to describe microscopic wetting phenomena. In this work, we hypothesize that a liquid–gas interface nano-bending, which is caused by the nonlinear coupling between the effects of the microscopic interface geometry and solid–liquid interactions, is responsible for this deviation. Simulation and theory: Using molecular dynamics simulations and mathematical modeling, we reveal the structure of the nano-bending and the mechanism of the nonlinear-coupled effect. We further apply our findings to illustrate a liquid microlayer with the saddle-shaped profile in nucleate boiling. Findings: The nonlinear-coupled effect is responsible for the deviation of a nano-droplet profile and also the very thin microlayer captured by different experiments. The saddle-shaped interface significantly highlights the nonlinear-coupled effect. The interface nano-bending, rather than the Young contact angle, acts as the boundary condition and dictates the liquid wetting system, especially for the case with high interface curvature. These findings provide insight into recent nano-scale droplet- and bubble-related wetting phenomena.

Original languageEnglish
Pages (from-to)813-822
Number of pages10
JournalJournal of Colloid and Interface Science
Volume630
DOIs
Publication statusPublished - 15 Jan 2023
Externally publishedYes

Keywords

  • Interface curvature
  • Liquid wetting
  • Microlayer
  • Nano-bending
  • Nano-bubble
  • Nano-droplet
  • Nonlinear-coupled effect
  • Nucleate boiling
  • Young contact angle

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Surfaces, Coatings and Films
  • Colloid and Surface Chemistry

Fingerprint

Dive into the research topics of 'Microscopic liquid–gas interface effect on liquid wetting'. Together they form a unique fingerprint.

Cite this