Nanotech 2014 Vol. 1
Nanotech 2014 Vol. 1
Nanotechnology 2014: Graphene, CNTs, Particles, Films & Composites

Nanostructured Coatings, Surfaces & Membranes Chapter 3

Bio-Inspired Multi-gradient Structure Surfaces for Water Collection/Repellency

Authors: Y. Zheng

Affilation: Beihang University, China

Pages: 233 - 236

Keywords: water collection, water repellency

Abstract:
Biological surfaces with micro- and nanostructures display unique wetting functions. Since spider silk collects water through a combination of multiple gradients in a periodic spindle-knot structure after wet-rebuilding process, a series of functional fibers with unique wettability have been designed and fabricated successfully by various improved techniques such as dip-coating, fluid-coating, tilt-angle coating, electrospun and self-assembly, to combine the Rayleigh instability theory. These geometrically-engineered thin fibers display a strong water capturing ability, directional driving of tiny droplets, a capable of intelligently responding to environmental changes in humidity, and also directional droplet transport in a long range. Otherwise, biological surfaces such as plant leaves and butterfly wings display water repellency. The suspending of microdroplets on a fresh lotus leaf is attributed to a gradient of wettable MNs along the exterior surface of papillae including nanohairs. The directional water repellency is achieved on wings of butterflies due to a flexibly oriented MN on wing. Also the MNs of wing generate low-temperature superhydrophobic properties. A MN thin flexible surface is fabricated, which displays excellent de-ice ability. In summary, these as-fabricated surfaces wil have promising applications in water-collecting, anti-icing, anti-frosting, or anti-fogging properties for practical applications in aerospace and industry.


ISBN: 978-1-4822-5826-4
Pages: 552
Hardcopy: $209.95