Purifying wastewater, however, requires a lot of energy – or does it? Not according to a South Korean research team.
Their multi-layered, printable membrane, which is not subject to size restrictions, could be used to generate electricity during the treatment process.
Because the top polymer layer is conductive. If water flows vertically onto it, ions in the liquid move horizontally, generating direct current.
The second membrane, at the bottom, then filters contaminants of less than 10 nanometres, including microplastics and heavy metal particles.
The team is currently working on a variant to make wastewater drinkable.
Meanwhile, a form of human ‘wastewater’ – sweat – is also a good energy supplier.