Anti-icing/icephobic coatings, typically applied in the form of surface functional materials, are considered to be an ideal selection to solve the icing issues faced by daily life and industrial production. However, the applications of anti-icing coatings are greatly limited by the two main challenges: bonding strength with substrates and stability of the high anti-icing performance. Here, we designed and fabricated a kind of high-performance superhydrophobic fluorinated silica (F-SiO 2 )@polydimethylsiloxane coatings and further emphasized the improvement of the bonding strength with substrates and the maintenance of high antiicing performance. The resultant coatings exhibited excellent water repellency with a contact angle up to 155.3°and a very short contact time (∼10.2 ms) of impact droplets. At low temperatures, the coming droplets still rapidly rebounded off the coating surface, and the superhydrophobic coatings displayed a more than 50-fold increase of freezing time comparing with bare aluminum. The ice adhesion strength on the coatings was only 26.3 kPa, which was far less than that (821.9 kPa) of bare aluminum. Furthermore, the nanoporous structures constructed by anodic oxidation could tremendously enhance the bonding strength of the coatings with the substrate, which was evaluated through a standard method (ASTM D3359). The anti-icing properties still retained high stability under the conditions of 30 icing/deicing cycles, soaking, and scouring of acid solution (pH = 5.6). This work can effectively push the anti-icing coatings toward a real-world application.

mightily appeal to many researchers to develop an anti-icing method without energy consumption by mimicking the plant surface topographies. [1][2][3][4][5][6] As well known, the famous Lotus Effect is widely used and induces to construct the hierarchical topography of composite micronanostructures in favor of entrapping more air pockets to repel water and finally realize the aim of preventing ice accumulation. [7][8][9][10][11] Also, many theoretical and experimental studies have been reported that the trapped air pockets play a thermal insulation role in preventing the freezing of supercooled water, and cause a remarkable reduction in solid/liquid contact area. [8,9,12,13] The resultant situation is that triggering ice nucleation gets more difficulty due to the increasing energy barrier, finally showing a certain extent of icingdelay performance. [14,15] Furthermore, the air pockets can be remained after freezing and serve as the original microcracks to reduce the ice adhesion strength, resulting in the adhered ice being extremely easily removed. [16][17][18] After a comprehensive insight into these reported literatures, the real anti-icing potential of hierarchical micro-nanostructure superhydrophobic surface needs to be further confirmed in the involved application environments due to the obvious distinction (several orders of magnitude) of the volume of reference supercooled droplets.We, therefore, made great efforts to verify the anti-icing capacity of hierarchical micro-nanostructure surfaces through modeling the application environments, not only the routine analyses in laboratory. Here, this work developed both routes to fabricate the superhydrophobic structure surfaces (see Figure 1a), hierarchical micro-nanostructure and single nanostructure surfaces, which were also labeled as hierarchical micronanostructure surface (HN-Surface) and single nanostructure surface (SN-Surface), respectively. The more detailed operating procedures are provided in Experimental Section. According to the previous experience and classical wetting theory, the HN-Surface is expected to entrap more air pockets underneath the droplets and exhibit more robust water repellence than the SN-Surface. [17,19,20] Also, the anti-icing performance should display the similar situation. The supercooled droplets on HN-Surface will take more time to complete the freezing process, and the produced ice can be easily removed under the action of slight external force due to the lower ice adhesion.Materials decorated by the hierarchical micro-nanostructures similar to lotus leaf surface topographies are firmly considered to possess the substantial anti-icing functions, showing icing-delay and low ice adhesion. Here, the aim of this work is to verify the anti-icing capacity in the actual icing environment containing supercooled airflow. This study, therefore, develops both routes to fabricate the hierarchical micro-nanostructure and single nanostructure superhydrophobic surfaces, and first evaluates their anti-icing capacity based on the routine mea...

Superhydrophobic coatings treated as surface functional materials are endowed with great application potential with respect to self-cleaning, drag-reduction, anti-icing, etc.

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