title: Wettability of partially suspended graphene.
abstract: The dependence of the wettability of graphene on the nature of the underlying substrate remains only partially understood. Here, we systematically investigate the role of liquid-substrate interactions on the wettability of graphene by varying the area fraction of suspended graphene from 0 to 95% by means of nanotextured substrates. We find that completely suspended graphene exhibits the highest water contact angle (85° ± 5°) compared to partially suspended or supported graphene, regardless of the hydrophobicity (hydrophilicity) of the substrate. Further, 80% of the long-range water-substrate interactions are screened by the graphene monolayer, the wettability of which is primarily determined by short-range graphene-liquid interactions. By its well-defined chemical and geometrical properties, supported graphene therefore provides a model system to elucidate the relative contribution of short and long range interactions to the macroscopic contact angle.
authors.affiliation: Nanosciences group, CEMES-CNRS, 29 rue Jeanne Marvig, Toulouse 31055, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Ondarçuhu
authors.affiliation: Nanosciences group, CEMES-CNRS, 29 rue Jeanne Marvig, Toulouse 31055, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Thomas
authors.affiliation: Nanosciences group, CEMES-CNRS, 29 rue Jeanne Marvig, Toulouse 31055, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Nuñez
authors.affiliation: Nanosciences group, CEMES-CNRS, 29 rue Jeanne Marvig, Toulouse 31055, France.
authors.forename: Erik
authors.initials: E
authors.lastname: Dujardin
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Atikur
authors.initials: A
authors.lastname: Rahman
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Black
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Antonio
authors.initials: A
authors.lastname: Checco