Surface Wettability Control

Lotous Leaf Effect

“Lotus leaf” has non-wetting property because of nano/micro scale roughness with surface wax coating. Biomimicking the “lotus leaf”, superhydrophobic surface exhibits outstanding water repellency because of fabricated micro/nano structure and coating with low surface energy materials. This non-wetting property could be used for many applications such as self-cleaning, oil/water separation, anti-fouling, anti-corrosion and drag reduction.

Superhydrophobic/superhydrophilic surface modification and application

To use the “lotus leaf effect”, we have synthesized various metal oxide nanowires (ZnO, WOx, SiC) and coated with self-assembled monolayers (-silane, -COOH and –thiol). At this time, we could change the surface wettability from hydrophilic to superhydrophobic by regulating the length of self-assembled monolayers. Using superhydrophopbic surface, we studied its stability in various conditions such as underwater and dynamic situations. To overcome the instability of superhydrophobic surface, we introduced photoelectrochemical cell for the first time. Besides this, we have studied various applications with superhydrophobic surface like drag reduction, anti-fouling and self-cleaning.

Slippery Liquid Infused Porous Surface (SLIPS)

“Nepenthes pitcher” also has non-wetting property because of slippery liquid existing on the porous surface. Biomimicking the “Nepenthes picher”, SLIPS (Slippery Liquid Infused Porous Surface) exhibits great non-wetting properties with not only water droplet but also other various liquids. By virtue of this property, SLIPS has been spotlighted as a new non-wetting property. In our laboratory, we have focused on anti-fouling surface to prevent the formation of biofilms using SLIPS.