Fabrication of bio-inspired non-fluorinated superhydrophobic surfaces with anti-icing property and its wettability transformation analysis

摘要

Ice accumulation leads to several inconvenient and even threatening situations in cold regions. This paper reports an efficient, non-toxic and low-cost method to fabricate hierarchical superhydrophobic surfaces on aluminum alloy with a water contact angle of 155 degrees and a sliding angle of 5 degrees. Tests were performed in an in-house apparatus to evaluate the ice adhesion strength and ice shear strength of the as-prepared surfaces and untreated aluminum surfaces. Results show that ice adhesion strength on different wettability surfaces strongly depends on the efficient specific surface area of the ice-solid interface. The ice shear strength was determined by different ice-solid interface contact shapes. Besides, the freezing delay time was recorded and different mechanisms of the icing process were analyzed by a specific simplified heat transfer model. The de-icing and self-cleaning test shows that the air cushion on the superhydrophobic surface can prevent the melted water from secondary icing and potential contaminations, especially at low temperature. Our results indicate that the as-prepared and recovered superhydrophobic surfaces present excellent anti-/de-icing properties and the special contact conditions and heat transfer process of the ice-substrate interface contribute to the anti-icing property of the superhydrophobic surface.