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Abstract Frosting occurs due to the freezing of condensed water droplets on a supercooled surface. The nucleated frost propagates through interdroplet bridges and covers the entire surface, resulting from the deposition of highly supersaturated vapor surrounding tiny droplets. While inhibition of the formation of frost bridges is not possible, the propagation of frost can be delayed by effectively removing tiny droplets. Passive technologies, such as superhydrophobic surfaces (SHS) and hydrophobic slippery liquid‐infused porous surfaces (SLIPS), rely on static growth and direct contact with densely distributed droplets. However, use of these approaches in delaying frost propagation involves challenges, as the interdroplet distance remains small. Here, we report a new approach of spontaneous droplet movement on hydrophilic SLIPS to delay the formation of interdroplet frost bridges. Surface tension forces generated by the hydrophilic oil meniscus of a large water droplet efficiently pull neighboring droplets with a diameter of less than 20 μm from all directions. This causes a dynamic separation between water droplets and an adjacent frozen droplet. Such a process delays the formation and propagation of interdroplet frost bridges. Consequently, there is significant delay in frosting on hydrophilic SLIPS compared to those on SHS and hydrophobic SLIPS.
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Robust hybrid diffusion control for long-term scalable frost prevention
Antifrosting surfaces are critical to the efficient and safe operation of infrastructure in cold and humid environments where deposition of frost (porous ice) is thermodynamically inevitable. Such infrastructure can include above-ground power cables and outdoor heat pumps. Here, we introduce a hybrid surface design that passively controls the diffusion of water vapor over a surface to sustain flat frost-free regions for long periods of time. We report more than 150 hours (~1 week) of frost prevention for a single hybrid unit cell, which is three orders of magnitude longer than reported frosting onset for other state-of-the-art techniques. We then demonstrate the potential for large-area frost prevention by scalable tessellation of unit cells and an intrinsic durability to scratches/cracks and physical contamination.
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- Award ID(s):
- 2337118
- PAR ID:
- 10557350
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 10
- Issue:
- 44
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.adq8525
