Superhydrophobic carbon nanotube/polydimethylsiloxane composite coatings

This paper reports a method for fabricating carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composite superhydrophobic coatings. With toluene as a solvent, the coating is obtained directly by spray of CNT/PDMS/toluene suspension. The hydrophobicity and micro-/nanostructure of the coatings are studied with respect to the mass ratio (MR) of CNT to PDMS. Based on the multiscale morphology analysis, it is shown that the nanoscale roughness is essential for achieving superhydrophobicity. To form nanoscale rough surface and obtain a stable superhydrophobic coating, MR>0.3 is recommended. In addition, such coatings also show small slide angle, low adhesion strength and long term stability of the coated surface. The method reported in this study is low cost and especially suitable for engineering applications.