Role of micrometric roughness on anti-ice properties and durability of hierarchical super-hydrophobic aluminum surfaces

A Novel Simple Anti-Ice Aluminum Coating: Synthesis and In-Lab Comparison with a Superhydrophobic Hierarchical Surface

“…Afterward, in order to generate a pseudo-boehmite nanostructured layer, the sample was boiled for 5 min at 100 • C in ultrapure water. Then, it was dried in air, rinsed with n-hexane and dried under nitrogen flux, as described in [12,26,27]. The obtained hierarchical substrate was dip-coated in the FAS bath (dipping-withdrawing speed: 0.7 mm/s, permanence time: 120 s) and cured at 70 • C for 1 h.…”

“…The novel coating shows very good anti-ice properties and relevant durability, with some differences from the fluorinated surface. The novel slippery coating process is promising for industrial applications, also taking into account its environmental compatibility, simplicity and low cost.Coatings 2020, 10, 111 2 of 17 scalable and industrially feasible process, for instance for the fabrication of cables for overhead power lines, is still an open issue.In a previous work, we studied a superhydrophobic surface obtained by applying a commercial fluoroalkyl silane (FAS) on a hierarchical micro-nano aluminum structure [12]. This coating maintained hydrophobic behavior even at low temperatures and evidenced amazing durability of ice-phobic properties after several freeze-thaw cycles in shear stress tests; however, the durability of this coating exposed in harsh environmental conditions was to be fully understood.…”

“…SLS has similar anti-icing, wettability and even better durability behavior of SLIPS, despite the considerable differences in the morphology and in the chemistry: indeed, the under-layer structure is a porous hydrophilic inorganic oxide, no lubricant is infused and the final surface is dry.The process to obtain the SLS is very intriguing because it is fast, environmentally friendly, economical, no special equipment and expensive chemicals are needed and thus could be easily transferred to industrial production. Although the process to grow the pseudo-boehmite is well known [25] and it is also very often used to build a nanostructure, as far as we know, a full characterization of durability and ice-phobicity of a surface similar to SLS is still missing.Results and performance in terms of hydrophobicity at room and low temperatures, ice adhesion forces and durability are compared with those of the superhydrophobic boehmite surface studied in our previous work [12]. This study aims to directly compare results obtained in the same laboratory, applying the same ice-phobic characterization methods and the same aging protocols, given that, so far, a recognized protocol to assess the durability of the coatings is missing.…”

“…In a previous work, we studied a superhydrophobic surface obtained by applying a commercial fluoroalkyl silane (FAS) on a hierarchical micro-nano aluminum structure [12]. This coating maintained hydrophobic behavior even at low temperatures and evidenced amazing durability of ice-phobic properties after several freeze-thaw cycles in shear stress tests; however, the durability of this coating exposed in harsh environmental conditions was to be fully understood.…”

“…Results and performance in terms of hydrophobicity at room and low temperatures, ice adhesion forces and durability are compared with those of the superhydrophobic boehmite surface studied in our previous work [12]. This study aims to directly compare results obtained in the same laboratory, applying the same ice-phobic characterization methods and the same aging protocols, given that, so far, a recognized protocol to assess the durability of the coatings is missing.…”