Slippery icephobic materials

slips_antiicing-200.jpg
We developed a scalable method to directly coat aluminum surfaces with a nanostructured polymer layer, subsequently converted into SLIPS. SLIPS can effectively delay ice accumulation and facilitate removal of ice even under high-humidity conditions.

Slippery Icephobic Materials

Slippery liquid-infused solid surfaces present a radically different approach to creating ice-repellent materials. State-of-the-art superhydrophobic surfaces frequently fail under high humidity, as the textures become coated with condensation and frost. The molecularly smooth liquid interface of SLIPS provides a comprehensive, integrated approach to ice prevention: the defect-free surface 1) enables incipient condensation droplets to slide off before they can freeze, 2) minimizes sites for ice nucleation, 3) ensures that free-sliding droplets freeze only in isolated patches rather than packed sheets, 4) minimizes ice adhesion, allowing frozen droplets to slide off under a small gravitational force, and 5) sheds droplets just as they start to thaw. 

Fig. 3: The smooth, defect-free SLIPS
The smooth, defect free SLIPS surface minimizes sites for ice to nucleate, compared to textured superhydrophobic surfaces (SHS). 

We have developed a technique for directly fabricating SLIPS on any metal surface, bringing SLIPS technology to refrigeration, aviation, marine vessels, wind turbines, wires, and many more metal-based applications. Aluminum (Al) in particular is widely used for cooling fins in heat exchangers and as a lightweight structural material, and we have demonstrated that SLIPS-coated Al surfaces not only suppress ice and frost accretion by efficiently removing condensed moisture even under high-humidity conditions, but also exhibit at least an order of magnitude lower ice adhesion than state-of-the-art anti-ice coatings. We are currently partnering with the refrigeration and aviation industries to develop new SLIPS-enabled, energy-efficient, and safe technologies.

Fig. 4: Free-sliding droplets that do freeze remain isolated, rather than merging into a large ice coating.
Condensation droplets slide off the SLIPS surface before they have a chance to grow or freeze. Free-sliding droplets that do freeze remain isolated, rather than merging into a continuous icy coating. Further, while the droplets do ultimately freeze at low temperatures, SLIPS minimizes ice adhesion and allows frozen droplets to slide off. 
Fig. 6: Thawing droplets
Thawing droplets are not pinned to the surface and can slide off upon a small increase in temperature. 

Publications

2013

Wilson P, Lu W, Xu H, Kim P, Kreder M, Alvarenga J, Aizenberg J. Inhibition of Ice Nucleation by Slippery Liquid-Infused Porous Surfaces (SLIPS). Physical Chemistry Chemical Physics. 2013;15:581–585. doi:10.1039/C2CP43586A
Wilson P, Lu W, Xu H, Kim P, Kreder M, Alvarenga J, Aizenberg J. Inhibition of Ice Nucleation by Slippery Liquid-Infused Porous Surfaces (SLIPS). Physical Chemistry Chemical Physics. 2013;15:581–585. doi:10.1039/C2CP43586A

2012

Kim P, Wong T, Alvarenga J, Kreder M, Adorno-Martinez W, Aizenberg J. Liquid-Infused Nanostructured Surfaces with Extreme Anti-Ice and Anti-Frost Performance. ACS Nano. 2012;6(8):6569–6577. doi:10.1021/nn302310q
Kim P, Wong T, Alvarenga J, Kreder M, Adorno-Martinez W, Aizenberg J. Liquid-Infused Nanostructured Surfaces with Extreme Anti-Ice and Anti-Frost Performance. ACS Nano. 2012;6(8):6569–6577. doi:10.1021/nn302310q

2011

Wong T-S, Kang SH, Tang S, Smythe E, Hatton B, Grinthal A, Aizenberg J. Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity. Nature. 2011;477:443–447. doi:10.1038/nature10447
Wong T-S, Kang SH, Tang S, Smythe E, Hatton B, Grinthal A, Aizenberg J. Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity. Nature. 2011;477:443–447. doi:10.1038/nature10447