Lotus bioinspired superhydrophobic, self‐cleaning surfaces from hierarchically assembled templates

Abstract

The super hydrophobic, self-cleaning properties of natural species derive from the fine hierarchical topography evolved on their surfaces. Hierarchical architectures which are function-mimetic of the lotus leaf are here described and created from multi-scale hierarchical assembled templates. The first level of hierarchy was a micromachined dome structure template and the second level of hierarchy was added by layering a thin nanoporous membrane such as porous anodized alumina or an ion track etch membrane. The assembled templates were nanoimprinted by a single step process on thermo-plastic films. The wetting angle of the surfaces reached a value of 160 and the self-cleaning behavior was observed. The superhydrophobic behavior remained over 1 year after fabrication, which demonstrates the stability of these polymeric selfcleaning topographies.

Superhydrophobic surfaces with photocatalytic activity under UV and visible light irradiation

“…Many different strategies for fabricating artificial superhydrophobic surfaces have been reported in the literature over the last decade. These include distribution of hydrophobic nanoparticles on solid surfaces [5][6][7] and micro-and nano-structuring of flat surfaces combined with surface termination with hydrophobic molecules [8][9][10][11]. Superhydrophobic surfaces have drawn particular attention due to their unique self-cleaning behaviors, as dust particles on superhydrophobic surfaces can be swept away by water droplets on the surface [7,[12][13][14].…”

Nanostructured Free‐Form Objects via a Synergy of 3D Printing and Thermal Nanoimprinting

“…Highly precise, ordered, and uniform surface patterns that cut across the micrometer and nanometer length scales offer a high degree of tunability for physical surface engineering. Surface properties such as wettability, friction/adhesion, and optical effects are some of the most frequently encountered properties in applications ranging from biomedical products (sensors, diagnostic devices) to optoelectronic devices and consumer products . Highly deterministic surface textures that lead to highly tunable surface properties offer a promising surface engineering approach for multiple reasons: 1) preserves the native chemical structure of the materials, 2) minimizes the use of chemical, thus offering a more sustainable approach for surface engineering, 3) multiple surface properties can be achieved through surface texturing, and 4) in nanometer scale surface texture, optical transparency of the material can be preserved.…”

Robust Polypropylene Fabrics Super-Repelling Various Liquids: A Simple, Rapid and Scalable Fabrication Method by Solvent Swelling

“…Templating or laminating exfoliation is a widely used technique to fabricate superhydrophobic PP materials. [36][37][38][39] For example, Hsu et al constructed artificial Γ-shape hairs via membrane casting. 36 Similarly, template of PTFE-coated-sieves was used.…”