By studying how the slippery surfaces of pitcher plants (Nepenthes) make an insect’s escape a lost cause, Harvard University researcher Joanna Aizenberg and colleagues have invented a self-cleaning, non-stick surface. The surface is both hydrophobic and oleophobic, so that both water- and oil-based liquids slide right off.The researchers found that the pitcher plant’s leaves have a spongelike texture infused with water that repels the sticky oils produced by insects’ feet. They have mimicked this by immobilizing a “lubricating film” inside nano/microstructured substrates to produce a smooth and highly slippery surface. The lubricating film can be chosen for its properties relevant to the use. In addition, they state that the properties of their substrates are insensitive to the precise geometry of the underlying substrate, making their approach applicable to various inexpensive, low-surface-energy structured materials (such as porous Teflon membrane).Potential applications include making oil flow more efficiently thorugh pipes, use on aircraft wings or industrial freezers (because it repels ice), self-cleaning surfaces, food or other product containers that efficiently shed contents, biomedical devices, or even an anti-graffiti surface.
There might be concerns over the use of nano-structures, the choice of lubricating fluids, and the recyclability of the product. One sustainability advantage of an omniphotic surface is that by being self-cleaning, it reduces the need to use chemicals and a lot of water to clean the surface, whether it’s the inside of a bottle or the surface of an airplane. Moving oil more efficiently through a pipeline might reduce the chance for biofilm buildup and therefore corrosion.
Read about how the researchers invented SLIPS using biomimicry in Zygote Quarterly:Edit Summary