Wetting dynamics under periodic switching on different scales: characterization and mechanisms

The development of substrates with a switchable wettability is proceeding and the limit of switching frequencies and contact angle differences between substrate states has developed in the past years. In this paper we investigate the behavior of a droplet on a homogeneous substrate, which is switched between two wettabilities for a large range of switching frequencies. Here, we are particularly interested in the dependence of the wetting behavior on the switching frequency. We show that results obtained on the particle level via molecular dynamics simulations and on the continuum level via the thin-film model are consistent. Predictions of simple models as the molecular theory of wetting (MKT) and analytical calculations based on the MKT also show good agreement and offer deeper insights into the underlying mechanisms.

Automated summary

This paper investigates the behavior of a droplet on a homogeneous substrate, which switches between two wettability states for a large range of switching frequencies. The results obtained from molecular dynamics simulations and the thin-film model are consistent. Simple models like the molecular theory of wetting and analytical calculations based on it also show good agreement and provide deeper insights into the underlying mechanisms.