Plasma modification of carbon nanowalls induces transition from superhydrophobic to superhydrophilic

Graphene-based materials play an essential role in a wide range of modern technologies due to their surface properties such as adsorption capacity and controllable wettability, which depend on the production methods. For practical applications, it is crucial to control the surface properties to achieve the desired wetting characteristics, which can be described with the contact angle (CA). Here, we experimentally investigate the wettability properties of the carbon nanowalls and show how to manage a wetting transition from superhydrophobic to superhydrophilic states. A CA of 170 degrees was reached with direct plasma synthesis, while an angle smaller than 20 degrees was achieved during the atmosphere plasma modification. Combining the formation of the surface groups due to the plasma treatment results and the macroscale wetting behavior in terms of the Cassie-Baxter model, we qualitatively explain how the observed wetting enhancement is induced by both controlled chemical and geometrical surface-heterogeneity.

Automated summary

Graphene-based materials play a crucial role in modern technologies due to their surface properties, which can be controlled through different production methods. This study experimentally investigates the wetting properties of carbon nanowalls and demonstrates a wetting transition from superhydrophobic to superhydrophilic states. The observed wetting enhancement is qualitatively explained by the combination of controlled chemical and geometrical surface-heterogeneity induced by plasma treatment.