Long-term and thermally stable superhydrophobic surfaces of carbon nanofibers.

Carbon nanofibers were prepared from polyvinyl alcohol (PVA) by a simple wetting-compatible method. The surfaces of the aligned carbon nanofibers show excellent thermal- and time-stable superhydrophobicity. The average water contact angle (CA) values are about 153.1+/-2.2 degrees at room temperature, with little difference coming from experimental error. In addition, the CA of the aligned carbon nanofibers surface maintains 139.1+/-3.2 degrees after 10 months of exposure to the ambient environment. Nanostructure on the surface of carbon nanofibers and the intrinsic thermal resistance of carbon contribute to this unique surface property.