Transparent coating from Tan Trao University uses conical protuberances and paraffin wax to reduce ice formation.

Benefits

  • Increased water repellency
  • Reduced frost formation

Applications

  • Automobiles
  • Aviation

UN Sustainable Development Goals Addressed

  • Goal 12: Responsible Production & Consumption

The Challenge

Frost is a common problem that can occur on a variety of surfaces. In the airline industry, flights can be grounded by even the slightest layer of frost on the windshield or wings of the aircraft. Frost on airplane wings can create drag, making flight dangerous or even impossible. Reduced frost formation would result in fewer cancelled flights and less use of strong deicing chemicals.

Innovation Details

The anti-icing surface is made of a thin layer of paraffin wax that lays over a textured quartz surface. The surface texture consists of uniform truncated cones with a height of 500 nm, similar to cones on the surface of moth eyes. The paraffin wax creates a hydrophobic surface with low thermal conductivity that prevents water droplets from sticking and freezing.

Image: Nguyen Ba Duc / Tan Trao University / Copyright © - All rights reserved

Material fabrication and SEM images. Photo: Nguyen Ba Duc/Tan Trao University.

Image: Nguyen Ba Duc / Tan Trao University / Copyright © - All rights reserved

Ice formation on varying levels of surface treatment. The top row is barely coated, the middle row has nanostructures, and the bottom row is coated with paraffin and has nanostructures. Photo: Nguyen Ba Duc/Tan Trao University.

Biomimicry Story

Moths hunt at dusk or at night when limited light is available. In order to maximize light capture, moths have unique sub-wavelength structures coating their eyes which dramatically minimize light reflection over a broad range of wavelengths. The outer surfaces of moth corneal lenses are covered with a regular pattern of conical protuberances. These protuberances reduce light reflection by creating a refractive index gradient between the air-lens interface, more gradually transitioning the change in light speed between the air and eye, thus minimizing reflection.