Statics and dynamics of nanodroplet electrowetting on an isothermally heated nanostructured surface
Journal
Journal of Molecular Liquids
Journal Volume
342
Date Issued
2021
Author(s)
Abstract
The statics and dynamics of electrowetting of a water nanodroplet on an isothermally heated nanostructured surface subjected to a vertical electric field are investigated via molecular dynamics (MD) simulations. The simulation results reveal that when imposing a constant electric field on the water nanodroplet, the static and dynamic contact angles of the water nanodroplet are always decreased with increasing the substrate temperature. At the same time, the spreading becomes faster at higher substrate temperatures. In the no-temperature-difference scenario, the statics and dynamics of electrowetting are found to strongly depend on the field strength and direction owing to small droplet sizes. Intriguingly, this dependence weakens with increasing the substrate temperature even completely disappears at high enough substrate temperatures. The result in the finite-temperature-difference scenario can be attributed to the weakened pining effect caused by vigorous evaporation in the vicinity of the contact line as well as the decreased liquid–vapor interfacial tension (or increased spreading coefficient) arising from the elevated interface temperature. ? 2021 Elsevier B.V.
Subjects
Electrowetting
Evaporation
Hydrogen bonds
Nanodroplet
Pinning
Electric fields
Isotherms
Molecular dynamics
Nanostructured materials
Dynamic contact angle
Nano-droplets
Nanostructured surface
Static contact angle
Statics and dynamics
Substrates temperature
Vertical electric fields
Water nanodroplets
Wetting
SDGs
Type
journal article