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Nanomat 2019 Nano Research & Applications
ISSN: 2471-9838 Page 39
January 28-29, 2019
Barcelona, Spain
18th Edition of International Conference on
Emerging Trends in
Materials Science and
Nanotechnology
Nano Res Appl 2019, Volume 5
DOI: 10.21767/2471-9838-C1-031
Biological surfaces create the enigmatical reality to be
contributed to learning of human beings. Such biological
surfaces with multi-gradient micro and nanostructures (MN)
display unique wetting functions in nature, which have inspired
researchers to design originality of materials for promising
future. In nature, a combination of multiple gradients in a
periodic spindle-knot structure take on surface of spider silk
after wet-rebuilding process in mist. This structure drives tiny
water droplets directionally toward the spindle-knots for highly
efficient water collection. Inspired by the roles of gradient MNs
in the water collecting ability of spider silk, a series of functional
fibers with unique wettability has been designed by various
improved techniques such as dip-coating, fluid-coating, tilt-
angle coating, electrospun and self-assembly to combine the
Rayleigh instability theory. The geometrically engineered thin
fibers display a strong water capturing ability than previously
thought. The bead-on-string heterostructured fibers are capable
of intelligently responding to environmental changes in humidity.
Also, a long-range gradient step spindle knotted fiber can be
driven droplet directionally in a long range. An electrospun fiber
at micro-level can be fabricated by the self-assembly wet-rebuilt
process, thus the fiber displays strong hanging-droplet ability. The
temperature or photo or roughness responsive fibers can achieve
a controlling on droplet driving in directions, which contribute to
water collection in efficiency. Besides, inspired by gradient effects
on butterfly wing and lotus leaves, the surfaces with ratchet MN,
flexible lotus-like MN are fabricated successfully by improved
methods, which demonstrate that the gradient MN effect rises
up distinctly by anti-icing, ice-phobic and de-ice abilities. These
multifunctional materials can be designed and fabricated for
promising applications such as water-collecting, anti-icing, anti-
frosting, or anti-fogging properties for practical applications in
aerospace, industry and so on.
Bioinspired micro and nanostructured surfaces
with controllable dynamic wettability
Yongmei Zheng
Beihang University, China