Superhydrophobic graphenic carbon nanowalls fabricated by one-step PECVD

Graphenic carbon nanowalls (GCNWs) were prepared on Quartz, silicon and silicon dioxide by plasma enhanced chemical vapor deposition (PECVD), respectively, and the superhydrophobicity was obtained after the surface modification with triethoxyoctylsilane (KH-832). Then, the effect of the preparation pressure (30, 40 and 50 Pa) on the wetting properties of GCNWs on Si substrate was investigated. It is found that the water contact angle (CA) of GCNWs fabricated at 50 Pa without the surface modification are 155°, which means that the superhydrophobic GCNWs can be obtained by just optimizing PECVD preparation parameters. The increase of GCNWs hydrophobicity with the PECVD base pressure could be attributed to the increased size of the nanosheets on GCNWs and the decreased surface free energy. The facile one-step fabrication of superhydrophobic surface provides a novel method to control the hydrophobicity of GCNWs, and the superhydrophobic GCNWs may serve as an important candidate for the fabrication of microfludic devices and embedded biomaterials.