论文部分内容阅读
Superhydrophobic surfaces,with water contact angles greater than 150° and sliding angles below 10°,are of wide interests for applications.Many methods have been developed to produce superhydrophobic surfaces,including anodic oxidation,electrochemical deposition,chemical etching and self-assembly,have been applied to fabricate super-hydrophobic surfaces.As aluminum alloy is widely used in many industrial fields,the fabrication of superhydrophobic of aluminum alloy surfaces has attracted much attention largely.Numerous methods,such as anodic oxidation,electrochemical etching and chemical etching method,have been developed to fabricate super-hydrophobic surfaces on the substrates.However,few studies have attempted to fabricate superhydrophobic surfaces with different metal films on aluminum alloy substrates.This is a shortcoming,because the Ag,Co,Ni and Zn are of great interest in the micro/nano electromechanical systems(MEMS/NEMS).In this work,we fabricated superhydrophobic surfaces on aluminum alloy substrate by using general galvanic replacement route to produce metal hierarchical micro/nanostructures(Ag,Ni,Co and Zn)and then lowering the surface energy by fluoroalkyl silane.To deposit metal micro/nanostructures of metals Ag,Ni,Co and Zn,0.1 M NH4F solutions containing the corresponding water-soluble salts(AgNO3,NiSO4,CoSO4 and ZnAc2)with the concentration of 10 mM were used.The Al plate was immersed into the above solutions at room temperature for 2 h.After deposition,the plate was rinsed with water and dried in air.Finally,the as-prepared films were immersed in an ethanol solution of fluorinated silane(FAS,1H,1H,2H,2H-perfluorooctadecyltrichlorosilane)for 60 min.In summary,a simple method to fabricate superhydrophobic surfaces with different metal structure was studied in this work.Scanning electron micrometry(SEM)shows that the surface morphology of the films exhibit micro/nanostructures.After depositing fluoroalkyl silane film,the superhydrophobic surface with a water contact angle of 160° and a sliding angle of 4°.