Australian researchers have developed a new nanowrinkled coating that could save the Australian shipping industry from millions spent in combating marine biofouling.
An undertaking of the University of Sydney Nano Institute, the nanostructured surface coatings come with anti-fouling properties – minus any toxic components.
According to the institute, biofouling is a huge economic issue, costing the aquaculture and shipping industries billions of dollars a year in maintenance and extra fuel usage.
The need for new anti-fouling agents has become all the more paramount ever since tributyltin was banned worldwide.
The Sydney team has been researching on non toxic agents for some time now. As team lead and Associate Professor Chiara Neto says: “We are keen to understand how these surfaces work and also push the boundaries of their application, especially for energy efficiency. Slippery coatings are expected to be drag-reducing, which means that objects, such as ships, could move through water with much less energy required.”
The new materials were tested tied to shark netting in Sydney’s Watson Bay, showing that the nanomaterials were efficient at resisting biofouling in a marine environment.
The new coating uses ‘nanowrinkles’ inspired by the carnivorous Nepenthespitcher plant. The plant traps a layer of water on the tiny structures around the rim of its opening. This creates a slippery layer causing insects to aquaplane on the surface, before they slip into the pitcher where they are digested.
Biofouling can occur on any surface that is wet for a long period of time, for example aquaculture nets, marine sensors and cameras, and ship hulls. The slippery surface developed by the Neto group stops the initial adhesion of bacteria, inhibiting the formation of a biofilm from which larger marine fouling organisms can grow.
According to the researchers, the antifouling coatings are mouldable and transparent, making their application ideal for underwater cameras and sensors.
Image credits and content: CoatingPaint/University of Sydney Nano Institute