Gold microstructure substrate with tunable wettability

Context

Scientists have developed a gold microstructure substrate with the ability to repel water as well as bubbles with tunable wettability.

Gold microstructure substrate

• The substrate showed hydrophobic nature, which gets magnified when coated with a self-assembled monolayer of octadecane thiol - a water-soluble sulfur compound with a carbon alkyl chain.
• The coating results in a reduction in surface energy, which in turn facilitates an enhancement in hydrophobic behaviour.
• Underwater wettability investigations on the substrate showed that it mainly repelled bubbles and when functionalised with coating of octadecanethiol, it repels mainly oil.

How the development is significant?

• It can be used in designing microfluidic devices, biosensors and useful in water transportation and self-cleaning.

What is Wettability?

• Wettability is the ability of a liquid to maintain contact with a solid surface.
• It is an important property in surface and interface science.
• Its influence is seen in many biochemical processes, sensing, microfluidics, water transportation, self-cleaning, industrial processes.
• The tunable wettability results from tunability in surface energy of the substrate, which can be utilized to regulate the direction of flow in water transportation and self-cleaning applications.