A Superhydrophobic Anti-Icing Surface with a Honeycomb Nanopore Structure

Recently, the icing disaster of transmission lines has been a serious threat to the safe operation of the power system. A superhydrophobic (SHP) anti-icing surface with a honeycomb nanopore structure was constructed using anodic oxidation technology combined with a vacuum infusion process. When the current density was 87.5 mA/cm2, the honeycomb porous surface had the best superhydrophobic performance (excellent water mobility), lowest ice-adhesion strength (0.7 kPa) and best anti-frosting performance. Compared with other types of alumina surfaces, the ice-adhesion strength of the SHP surface (87.5 mA/cm2) was only 0.2% of that of the bare surface. The frosting time of the SHP surface (87.5 mA/cm2) was 150 min, which was much slower. The former is attributed to the air cushion within the porous structure and the stress concentration, and the latter is attributed to the self-transition of the droplets and low solid-liquid heat transfer area. After 100 icing or frosting cycles, the SHP surface (87.5 mA/cm2) maintained a low ice-adhesion strength and superhydrophobic performance. This is because the anodic oxidation process forms a hard porous film, and the nano porous structure with a high aspect ratio can store modifiers to realize self-healing. The results indicate that the SHP surface with a honeycomb nanopore structure presents excellent anti-icing performance and durability.