Nanodroplets Impacting on Graphene

TL;DR

This study uses molecular dynamics simulations to investigate how water nanodroplets interact with graphene, revealing that wettability depends on droplet velocity and can vary from hydrophobic to hydrophilic, helping clarify conflicting reports.

Contribution

It demonstrates that graphene's wettability is influenced by droplet impact velocity, providing a dynamic perspective on its surface properties.

Findings

Contact angles vary from 86° to 35° depending on droplet velocity.

Wettability of graphene is influenced by spreading liquid dynamics.

Results help explain inconsistencies in previous literature.

Abstract

The unique and remarkable properties of graphene can be exploited as the basis to a wide range of applications. However, in spite of years of investigations there are some important graphene properties that are not still fully understood, as for example, its wettability. There are controversial reported results whether graphene is really hydrophobic or hydrophilic. In order to address this problem we have carried out classical molecular dynamics simulations of water nanodroplets shot against graphene surface. Our results show that the contact angle values between the nanodroplets and graphene surfaces depend on the initial droplet velocity value and these angles can change from 86 degrees (hydrophobic) to 35 degrees (hydrophilic). Our preliminary results indicate that the graphene wettability can be dependent on spreading liquid dynamics and which can explain some of the apparent inconsistencies reported in the literature.