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Influence of surface roughness on superhydrophobicity

C. Yang·U. Tartaglino·B. N. J. Persson
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Abstract

Superhydrophobic surfaces, with liquid contact angle theta greater than 150 degree, have important practical applications ranging from self-cleaning window glasses, paints, and fabrics to low-friction surfaces. Many biological surfaces, such as the lotus leaf, have hierarchically structured surface roughness which is optimized for superhydrophobicity through natural selection. Here we present a molecular dynamics study of liquid droplets in contact with self-affine fractal surfaces. Our results indicate that the contact angle for nanodroplets depends strongly on the root-mean-square surface roughness amplitude but is nearly independent of the fractal dimension D_f of the surface.

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C. Yang, U. Tartaglino, B. N. J. Persson. 2006-09-30. Influence of surface roughness on superhydrophobicity. https://doi.org/10.1103/physrevlett.97.116103

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