Water Droplet Bouncing and Superhydrophobicity Induced by Multiscale Hierarchical Nanostructures

Abstract

Superhydrophobicity of multiscale hierarchical structures and bouncing phenomenon of a water droplet on the superhydrophobic surface were studied. The multiscale hierarchical structures of carbon nanotube/ZnO and ZnO/carbon nanofiber were produced by the hydrothermal method. The multiscale hierarchical structure showed superhydrophobicity with a static contact angle (CA) larger than 160° due to increased air pockets in the Cassie-Baxter state. The water bouncing effect observed on the multiscale hierarchical nanostructure was explained by the free energy barrier (FEB) analysis and finite element simulation. The multiscale hierarchical nanostructure showed low FEBs which provoke high CA and bouncing phenomenon due to small energy dissipation toward receding and advancing directions.

The fabrication of stable superhydrophobic surfaces using a thin Au/Pd coating over a hydrophilic 3C-SiC nanorod network

“…Superhydrophobicity is generally achieved by creating highly rough fractal surfaces and multiscale hierarchical micro/nano structures and further reducing the surface energy by chemical modifications using hydrophobic coatings [1][2][3][4][5][6][7][8][9]. Generally, fluoropolymers, are used to further modify as-grown micro/nanostructured surfaces to achieve superhydrophobicity.…”

A general, rapid and solvent-free approach to fabricating nanostructured polymer surfaces

“…The wettability/CA of all the other polymers in our experiments shows similar trends, except that nanostructured PMMA and PP surface are highly hydrophobic other than superhydrophobic (Figure 4(b)). The underlying physical chemistry of wettability regulation may be attributed to the roughness of nanostructured polymer surface [31]. Briefly, the length of polymer fibers increases with t w , which results in increased surface roughness and in turn enables polymer surfaces to provide more air pockets between polymer fibers and to maintain the Cassie-Baxter state [32]; consequently, the nanostructured polymer surfaces show improved hydrophobicity.…”

Segmented polymer nanowires and nanorods by one-step template wetting with a hyperbranched polymer and linear polymer blend

“…Till now, only a limited number of studies on the impact effect have been reported. [28][29][30][31] Here, we investigated the impact behavior based on our previous work about impact dynamics of droplets. 32 Fig.…”