Using GRAPHENE-oxide membrane as a filtration technique has a certain limitation: if immersed in water, the membrane becomes slightly swollen which allows smaller salts to flow along with water and the larger ions to be blocked.
Researchers at the National Graphene Institute in The University of Manchester discovered this a long time ago, and now they have provided a solution to bypass this problem.
By developing a strategy to avoid the swelling of the graphene-oxide membrane, they have opened possibilities in sieving common salts from seawater and make the water potable. Ultimately, they created an opportunity to provide clean drinking water to more than a billion people around the world. Their solution involved controlling precisely the pore size in the graphene-oxide membrane. In this manner, more salts are filtered out of the seawater making it safe to drink.
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