Surfaces could be cleaning themselves soon

Researchers at MIT and in Saudi Arabia have created a new way of making surfaces that actively control how fluids move across them.

The discovery may enable new varieties of biomedical, microfluidic devices or solar panels that can clean themselves, according to a report by MIT News.

“Most surfaces are passive,” said Kripa Varanasi, senior author of a paper describing the system in Applied Physics Letters. “They rely on gravity, or other forces, to move fluids or particles.”

The system uses a microtextured surface with bumps and ridges and a fluid that can be manipulated. When droplets of water or tiny particles touch the surface they are coated.

The magnetised coat can actually pull the unwanted particles across the surface. The new system’s slippery surface means that fluids and particles can move around with virtually no friction.

“This allows us to attain high velocities with small applied forces,” said Karim Khalil, the lead author.

While the initial test uses a magnetic fluid, the team believes that the same principle could be used when using other forces such as electric field or temperature differences.

Watch a droplet being pulled with magnetic forces: