Anti-icing performance of transparent and superhydrophobic surface under wind action

In this work, we demonstrated the anti-icing properties of a transparent and superhydrophobic coating surface based on the octadecyltrichlorosilane-modified silica nanoparticles. The surface was prepared via a simple condensation polymerization followed by a spray-coating process. The surface exhibited a high contact angle of 157.5° and a low sliding angle of 6.5° at ambient temperature. The icing behavior of the surface was investigated by successively dropping the 0 °C of water droplets onto the superhydrophobic coating surface at various low temperatures, i.e., –5, –10 and –15 °C with the help of wind action. The surface displayed excellent anti-icing properties at –5 and –10 °C. Water droplets bounced off or slid away the surface before freezing under wind action at the above temperatures. The icing delay time is larger than 2500 s at –10 °C and 5 m/s of wind blow. While at even lower temperature of –15 °C, water froze on the surface quickly. The icing and/or anti-icing mechanisms of the superhydrophobic surface at different temperatures were interpreted by the variation of the surface wettabilities with decreasing temperatures. Specifically, the humidity in air condensed and consequently formed a layer of frost covering the superhydrophobic surface, which has significant influence on the moving abilities of the surface water droplets. As a result, the anti-icing properties of the coating surface changed with the decreasing of temperatures.