Preparation of a biomimetic superhydrophobic ZnO coating on an X90 pipeline steel surface
Abstract
Inspired by the self-cleaning property of the lotus leaf surface, a novel biomimetic coating with superhydrophobicity is introduced in this article. Moreover, the morphologies, crystal structures and chemical composition of the specimens were investigated using field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). After electrodeposition of the Zn coating, a ZnO coating with micro and nano structures (perpendicular to the substrate surface) was obtained on an X90 pipeline steel surface after it was processed with the appropriate hydrothermal treatment time. The water contact angle (CA) of the ZnO coating, which had upright micro and nano structures, was about 137.85° without chemical modification. After further modification with a low-surface-energy material, the ZnO coating presented superhydrophobicity with the water CA of 157.59° and the sliding angle (SA) was less than 10°. Therefore, this study changed the traditional application of the deposited coating that was mostly used as a protective layer and might open up a new application field for deposited metal coatings to fabricate microstructures with functional applications, including superhydrophobic coatings.