Rational fabrication of fluorine-free, superhydrophobic, durable surface by one-step spray method

Abstract

The role of superhydrophobic coating in metal anti-corrosion, oil leakage treatment, waterproofing and antifouling cannot be overstated, yet the application of conventional superhydrophobic coatings is limited due to their toxicity, poor mechanical stability, and high cost. Herein we report our design on an eco-friendly wax-derived organic-based superhydrophobic coating based on self-designed sol and eco-friendly wax and integrated the spray coating technique. The W-GPAC coating exhibits superhydrophobicity (Contact Angle: 170.6°, Sliding Angle: 5.3°) with a glass substrate. It should be noted that the coating could preserve excellent superhydrophobic property in water spray impact test (Contact Angle:160° after 500 water impact cycles), linear abrasion test(Contact Angle:160° after 120 cm linear abrasion), and acid-base durability test (Contact Angle: greater than 165° after immersion in the acidic or alkaline environment for 600 min). In addition, the coating maintains outstanding adhesion with various substrates even at freezing treatment. The superior performance of the coating comes from the folded structure formed by the drying of GPAC sol which is formed by the dense siloxane crosslinking network of GPAC sol and long-chain silane on the coating surface. Taken together, the W-GPAC superhydrophobic coating enjoys low manufacturing cost, easy degradability, and no secondary pollution, and can be applied to almost commonly used substrates with superior mechanical durability, which could provide alternative solution for superhydrophobic application.