Passive anti-icing surfaces, or icephobic surfaces, are an area of great interest because of their significant economic, energy and safety implications in the prevention and easy removal of ice in many facets of society. The complex nature of icephobicity, which requires performance in a broad range of icing scenarios, creates many challenges when designing ice-repellent surfaces. Although superhydrophobic surfaces incorporating micro- or nanoscale roughness have been shown to prevent ice accumulation under certain conditions, the same roughness can be detrimental in other environments. Surfaces that present a smooth liquid interface can eliminate some of the drawbacks of textured superhydrophobic surfaces, but additional study is needed to fully realize their potential. As attention begins to shift towards alternative anti-icing strategies, it is important to consider and to understand the nature of ice repellency in all environments to identify the limitations of current solutions and to design new materials with robust icephobicity.
The authors thank A. Grinthal and K.-C. Park for their comments on the manuscript. M.J.K. thanks Natural Sciences and Engineering Research Council (NSERC) for a Postgraduate Scholarships-Doctoral (PGS D) scholarship. The information, data, or work presented herein was funded in part by the Advanced Research Projects Agency-Energy (ARPA‑E), US Department of Energy, under Award Number DE‑AR0000326.