Water graphene contact surface investigated by pairwise potentials from force-matching PAW-PBE with dispersion correction

by Li, Jicun; Wang, Feng

A pairwise additive atomistic potential was developed for modeling liquid water on graphene. The graphene-water interaction terms were fit to map the PAW-PBE-D3 potential energy surface using the adaptive force matching method. Through condensed phase force matching, the potential developed implicitly considers the many-body effects of water. With this potential, the graphene-water contact angle was determined to be 86 degrees in good agreement with a recent experimental measurement of 85 degrees +/- 5 degrees on fully suspended graphene. Furthermore, the PAW-PBE-D3 based model was used to study contact line hysteresis. It was found that the advancing and receding contact angles of water do agree on pristine graphene, however a long simulation time was required to reach the equilibrium contact angle. For water on suspended graphene, sharp peaks in the water density profile disappear when the flexibility of graphene was explicitly considered. The water droplet induces graphene to wrap around it leading to a slightly concave contact interface. Published by AIP Publishing.

Journal
Journal of Chemical Physics
Volume
146
Issue
5
Year
2017
URL
https://dx.doi.org/10.1063/1.4974921
ISBN/ISSN
1089-7690; 0021-9606
DOI
10.1063/1.4974921