Anti-frosting performance of superhydrophobic surface with ZnO nanorods

A superhydrophobic (SHP) surface is believed to be potential candidates for anti-icing/frosting applications. In this study, a SHP surface with ZnO nanorods was fabricated through radio frequency (RF) magneton sputtering method. The XRD pattern, surface morphology, wettability and chemical composition were characterized by corresponding methods. The anti-frosting property and mechanism of frost propagation on surfaces exhibiting various degrees of wettability were investigated on a Peltier-based platform. Compared with the bare glass surface and a permanent-room-temperature-vulcanized silicon rubber-coated glass surface, the as-prepared SHP ZnO surface displays excellent anti-frosting property. Frost formation on the as-prepared SHP ZnO surface was delayed for 140   min at −10   °C. A large gap free of condensed water droplets formed on the as-prepared SHP ZnO surface because of the self-propelled movement and absorption of condensed water droplets by the frost front. As a consequence, the frost propagation rate is effectively reduced. Moreover, after 30 cycles of frosting/defrosting process, no evident degradation of the as-prepared SHP ZnO surfaces was observed, indicating fair durability against repetitive frosting/defrosting process. Our study provides insights into the mechanism of anti-frosting property of nanostructured SHP surfaces and proposes a potential method to fabricate an anti-frosting surface.