A team of mechanical engineers from University of Illinois has found a new solution for removing salt from sea-water to make it drinkable. This energy efficient material is a nano-meter thick sheet of Molybdenum Disulfide (MoS2) a material full of tiny holes called nanopores, best suited for the process of desalination. The Illinois research team created different models out of various thin-film membranes. Their results showed that MoS2 has the highest efficiency in that it could filter up to 70% more water than graphene membranes.

What is the existing method? What are it’s drawbacks?

Most of the existing solution for making sea water drinkable are based on the reverse osmosis process, where seawater is passed through a thin plastic membrane which separates the salt to give you clean, fresh water. Though this is an effective method, the amount of drinkable water produced is very little. Moreover, since these membranes are pretty thick, the desalination system needs to have a strong mechanism for pushing the water through it.

What’s New?

The Illinois team of researchers found that MoS2 nanopores were much better than graphene membranes at water desalination, thanks to its chemical properties, thinness and pore geometry. MOS2 has molybdenum in the center for attracting water, then there’s sulfur on the side to push it away and therefore water gets easily passed through it.

Moreover, with its natural thinness, the MoS2 single layer sheets don’t need much energy and therefore is great for reducing operating costs. Since it is a robust material, it’s great at withstanding high water volume pressure as well.