Preparation Of Graphene/Nickel Composite Super-hydrophobic Layer On Aluminum Substrate And Icephobic/Anti-icing Performance Study

Super-hydrophobic surface refers to the surface with a water contact angle greater than 150° and sliding angle less than 10°.In recent years,super-hydrophobic surface has attracted extensive attention because of its excellent self-cleaning properties,anti-icing and anti-corrosion properties.Aluminum,as the most abundant metallic element in nature,has been widely used in various fields.It is of great significance and practical values to prepare super-hydrophobic coating on aluminum surfaces.The fabricated super-hydrophobic surface is difficult to be practically used due to the poor mechanical stability and durability,and the method of partially fabricating the super-hydrophobic surface has high requirements on the equipment and the preparation process is relatively complicated.In this work,a simple electrodeposition method is used to fabricate a micronano hierarchical structure on aluminum substrates.After chemical modification with myristic acid,the as-prepared super-hydrophobic film exhibited good mechanical stability and long-term durability.Results are as follows:(1)The graphene/nickel composite layer with micro-nano hierarchical structure was successfully fabricated via electrodeposition method under the optimum conditions of current density of 20 mA/cm2,deposition time of 10 min and temperature of room temperature,in which graphene provided micron-sized convex structure and deposition of nickel formed acicular nano-sized convex structure.After chemical modification with myristic acid of 0.1 mol/L for 30 min,the composite layer have a CA of 155° and an SA of 3°.Water droplets contact area with gas up to 84.5%on the composite layer,and the surface has a self-cleaning performance.(2)The addition of graphene can significantly increase the roughness of the electrodeposited surface.The roughness of the graphene/nickel composite superhydrophobic surface,which was fabricated under the optimized conditions,is 15.3±0.8?m.After 40 cycles of sandpaper abrasion test,the super-hydrophobic surface has a CA of 154° and an SA of 5°.The fabricated super-hydrophobic surface has excellent mechanical stability and good durability.(3)The graphene/nickel composite super-hydrophobic surface which was fabricated by the optimal process conditions shows good anti-icing performance under the four temperature conditions of-5?,-10?,-15? and-20?,Compared with normal smooth aluminum flake,the quality of icing on super-hydrophobic surface is not obvious with the dripping time under the four low temperature conditions,and the quality of icing is still very small even at-20?.Meanwhile,super-hydrophobic surface also has the best delay icing performance(4)The quality of icing on the super-hydrophobic surface is affected by the dripping height.When the temperature is-5? and the dripping height is too high over 11 cm,the quality of ice coating on the super-hydrophobic surface will increase remarkably,while the critical height decreases with the decrease of temperature.But under the same conditions,the quality of icing on the super-hydrophobic surface is still lower than the quality of icing on the surface of normal smooth aluminum.The super-hydrophobic surface with micro/nano hierarchical structure has a performance of anti-icing/icephobic by both ways of promoting the water drop to roll off from the surface and delaying the freezing time of the water drop on the surface.