Bioinspired gradient surfaces: From design to functions on wettability

3^rd International Conference on Smart Materials & Structures

March 20-22, 2017 Orlando, USA

Yongmei Zheng

Beihang University, China

Keynote: J Material Sci Eng

Abstract :

Biological surfaces provide endless inspiration for design and fabrication of smart materials. It has recently been revealed to have become a hot research area in the materials science world. The capture silk of the cribellate spider Uloborus walckenaerius collects water through a combination of multiple gradients in a periodic spindle-knot structure after rebuilding. Inspired by the roles of micro- and nanostructures (MNs) in the water collecting ability of spider silk, a series of bioinspired gradient fibers has been designed by integrating fabrication methods and technologies such as dip-coating, Rayleigh instability break-up droplets, phase separation, strategies of combining electrospinning, electrospraying and web-assembly. Through such fabrications, spindle-knot/joint structures can be tailored to demonstrate the mechanism of multiple gradients (e.g., roughness, smooth, temperature-respond, photo-triggering, etc.,) in driving tiny water drops. A water capturing ability can be developed by the combination of slope and curvature effects on spindle-knots on bioinspired fiber. The heterostructured fibers have been fabricated by electrohydrodynamic strategies are intelligently responding to environmental humidity. A temperature-responsive fiber can realize the directional transport of droplet effectively. The multi-geometric gradient fiber achieves the droplet target transport in a long range along as-designed bioinspired gradient fiber. In contrast, biological surfaces such as plant leaves and butterfly wings with gradient structure features display the effect of water repellency. Smart bioinspired surfaces can be fabricated by combining machining, electrospinning, soft lithography and nanotechnology. The gradient surfaces exhibit robust transport and controlling of droplets. These bioinspired gradient surfaces would be promising applications into anti-icing, liquid transport, anti-fogging/self-cleaning, water harvesting, etc.

Biography :

Yongmei Zheng is currently a Professor at School of Chemistry and Environment, Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education in Beihang University, China. Her research interests are focused on bioinspired surfaces with gradient micro- and nanostructures to control dynamic wettability.

Email: zhengym@buaa.edu.cn