A Simple Method for Fabrication of Bionic Superhydrophobic Zinc Coating with Crater-like Structures on Steel Substrate

Surface modification with superhydrophobicity is a popular and challenging research field on metals. In this work, a simple method was used to fabricate a bionic superhydrophobic zinc coating with crater-like structures on pipeline steel surface. This method involved electrodeposition of zinc coating and chemical reaction in perfluorooctanoic acid ethanol solution. The perfluorooctanoic acid with low surface free energy was not only used for chemical etching but also used for fluorinated modification. The contact angle of water on such superhydrophobic zinc coating was up to 154.21 degrees, and the sliding angle was less than 5 due to the micro crater-like structures and the low surface free energy. Moreover, the prepared superhydrophobic zinc coating demonstrated excellent self-cleaning property and great stability at room temperature, and the contact angle of water on this coating remained stable after storage in air for more than 80 days. This superhydrophobic zinc coating will open much wider applications of electrodeposition metal coating, including self-cleaning property, and can be easily extended to other metals.