Physics Colloquium: Engineering surface microstructures for slippery, ultra-low adhesion and omniphobic surfaces; ice nucleation, bacterial attachment, and ketchup stains

Event Details

  • Speaker(s): Benjamin Hatton
  • Date:
  • Time: 4:00 PM
  • Location: MacN 101

Abstract

Recent years have shown a strong interest in non-wetting, ‘superhydrophobic’ surfaces, in which a rough, hydrophobic surface keeps the liquid interface at the tips of the surface features, with an air layer underneath. This type of surface – often seen in plant leaves, insects, and bird feathers – can be very stable against wetting, and sometimes even relatively low surface tension liquids. We have taken advantage of this surface property to control ice nucleation (and localized water condensation), crystal nucleation (CaCO3), and bacterial attachment.

Our recent work involves the development of a novel ‘omniphobic’ surface known as a Slippery Liquid-Infused Porous Surface (SLIPS) – these materials incorporate a thin layer of lubricant around a rough surface microstructure, which is energetically stable and is immiscible to other contacting liquids [1][2].

Therefore, any other liquids, proteins or bacteria - across a very wide range - can only ‘see’ this stable lubricant layer, and there is very little opportunity for adhesion. This design is very similar to the slippery surfaces of the carnivorous pitcher plant. We have demonstrated omniphobicity for a range of oils, low surface tension fluids, complex fluids and ice.

[1] T. S. Wong, S. H. Kang, S. K. Y. Tang, E. J. Smythe, B. D. Hatton, A. Grinthal, J. Aizenberg, Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity. Nature 477, 443 (2011).[2] N. Vogel, R. Belisle, B. D. Hatton, T. S. Wong, J. Aizenberg, Fully transparent, omniphobic surfaces and based on inverse colloidal monolayers, Nature Communications 4, (2013).