TY - JOUR
T1 - Wetting of water on graphene nanopowders of different thicknesses
AU - Bera, Bijoyendra
AU - Shahidzadeh, Noushine
AU - Mishra, Himanshu
AU - Belyaeva, Liubov A.
AU - Schneider, Grégory F.
AU - Bonn, Daniel
N1 - KAUST Repository Item: Exported on 2021-02-19
PY - 2018/4/12
Y1 - 2018/4/12
N2 - We study the wetting of graphene nanopowders by measuring the water adsorption in nanopowder flakes of different flake thicknesses. Chemical analysis shows that the graphene flakes, especially the thin ones, might exist in the partially oxidized state. We observe that the thinnest graphene nanopowder flakes do not adsorb water at all, independent of the relative humidity. Thicker flakes, on the other hand, do adsorb an increasing amount of water with increasing humidity. This allows us to assess their wetting behavior which is actually the result of the competition between the adhesive interactions of water and graphene and the cohesive interactions of water. Explicit calculation of these contributions from the van der Waals interactions confirms that the adhesive interactions between very thin flakes of graphene oxide and water are extremely weak, which makes the flakes superhydrophobic. “Liquid marble” tests with graphene nanopowder flakes confirm the superhydrophobicity. This shows that the origin of the much debated “wetting transparency” of graphene is due to the fact that a single graphene or graphene oxide layer does not contribute significantly to the adhesion between a wetting phase and the substrate.
AB - We study the wetting of graphene nanopowders by measuring the water adsorption in nanopowder flakes of different flake thicknesses. Chemical analysis shows that the graphene flakes, especially the thin ones, might exist in the partially oxidized state. We observe that the thinnest graphene nanopowder flakes do not adsorb water at all, independent of the relative humidity. Thicker flakes, on the other hand, do adsorb an increasing amount of water with increasing humidity. This allows us to assess their wetting behavior which is actually the result of the competition between the adhesive interactions of water and graphene and the cohesive interactions of water. Explicit calculation of these contributions from the van der Waals interactions confirms that the adhesive interactions between very thin flakes of graphene oxide and water are extremely weak, which makes the flakes superhydrophobic. “Liquid marble” tests with graphene nanopowder flakes confirm the superhydrophobicity. This shows that the origin of the much debated “wetting transparency” of graphene is due to the fact that a single graphene or graphene oxide layer does not contribute significantly to the adhesion between a wetting phase and the substrate.
UR - http://hdl.handle.net/10754/627573
UR - https://aip.scitation.org/doi/abs/10.1063/1.5022570
UR - http://www.scopus.com/inward/record.url?scp=85045303709&partnerID=8YFLogxK
U2 - 10.1063/1.5022570
DO - 10.1063/1.5022570
M3 - Article
AN - SCOPUS:85045303709
VL - 112
SP - 151606
JO - Applied Physics Letters
JF - Applied Physics Letters
SN - 0003-6951
IS - 15
ER -