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.