Superhydrophobicity or icephobicity for an effective icing mitigation strategy?

There is a growing interest and debate on the role of surface coatings to combat ice accretion on solid surfaces. Most of the studies have focused on "icephobicity", with the aim of either reducing ice adhesion strength or delaying freezing time. Here we present an alternative strategy, which relies on the superhydrophobicity of surfaces as a way to enhance liquid water shedding from a surface prior to water freezing. To show in which conditions liquid water drops can rebound and be shed from a solid surface before freezing, drop impact experiments were performed on solid targets characterized by different wettability and thermal properties. The main result is that, when frost formation is avoided on the surfaces (i.e. if surface temperature is above dew point), drop dynamics, including spreading and recoiling, remains unaffected by solidification effects. In particular, drop rebound can still be achieved down to-20°C.