The Relationship between Superhydrophobicity, Self-Cleaning Performance and Microstructure of Butterfly Wing

The microstructure and hydrophobicity of butterflywing surfaces were investigated by a scanning electron microscope (SEM), an atomicforce microscope (AFM) and a contact angle meter. The relationship between hydrophobicity,self-cleaning performance and microstructuralcharacteristic was analyzed. The butterfly wing surface is of lowadhesion (water SA 1~3°) and high hydrophobicity (water CA 138~157°). Theaverage rate of CaCO3 pollutionremoval from the wing surface is as high as 86.2%. There is a good positive correlation (R2=0.873)between pollution removal rate and roughness index of the wing surface. The coupling effects of hydrophobic material andrough microstructure contribute to the complex wettability and remarkableself-cleaning property of the wing surface. Butterfly wing can be potentiallyused as a template for design of micro-controllable superhydrophobic surfaceand nano self-cleaning material. This work may offer inspirations forbiomimetic fabrication of novel interfacial material with multi-functions.