Tuning wettability of graphene oxide surfaces by laser-induced reduction in liquid environment

Controlling surface wettability is a major technological challenge. In this work, we employ the laser scribing method to control the wettability of laser-reduced graphene oxide by using different liquid media. The measured contact angle can be tuned from 50° to 120°, driven by the thermal conductivity and the boiling point of the solvent. While the contact angle is slightly related to the oxygen content, we show that higher contact angle is related to a higher surface roughness of the surface. This is a fast and inexpensive method to produce surfaces with controlled wettability.