Researchers from MIT and the Oak Ridge national Laboratory (ORNL) developed a promising new graphene-based membrane that can be useful to filter microscopic contaminants from water or for drug delivery. The membrane features high flux and tunability (i.e. it can quickly filter fluids but also be easily tunable to let certain molecules through while stopping others).
To develop the membrane, the team fabricated a 25 square millimeter graphene sheet using CVD. They managed to transfer the sheet to a polycarbonate substrate dotted with holes. They thought that the graphene will be totally impermeable, but experiments proved that salts can flow through the membrane.
That's not the first research that studies graphene pores. A few weeks ago we reported that tiny graphene pores (less than one nanometer) are possible - which can be useful for DNA sequencing. Other researchers demonstrated that graphene membranes with tiny pores can effectively and efficiently separate gas molecules through size-selective sieving.