Researchers at the National University of Singapore (NUS) have created an aerogel that produces drinking water from the air around us.
The product was created by Ho Ghim Wei a professor from the NUS Department of Electrical and Computer Engineering, along with Gamze Yilmaz and Fan Lu Meng.
The NUS researchers published their creation in the journal Science Advances in October 2020.
Does not need an external power source
According to the Food and Agriculture Organization (FAO), about one-sixth of the world's population (or 1.2 billion people) live in severely water-constrained agricultural areas.
At the same time, the earth's atmosphere contains water that can fill almost half a trillion Olympic swimming pools.
To address this gap, the team led by Ho created a type of lightweight aerogel that absorbs water from the air and does not need a battery or an external power source.
One kg of aerogel can produce 17 litres of water in a day
In a humid environment, one kilogram of aerogel can produce 17 litres of water in a day.
This could meet a household's daily water needs.
The gel also does not have to be squeezed to release the water it absorbs from the air.
The water from the aerogel has also been tested and meets the World Health Organization’s standards for drinking water.
How does it work?
Inside the aerogel, there are long-chain polymers (which are long, snakelike structures) that can switch between attracting water and repelling water.
This allows for the 'smart' aerogel to independently gather water molecules from the air, and then condense them into a liquid to release the water it has absorbed.
With sunlight, the structure can transform into a state where 95 per cent of the water vapour that goes into the aerogel comes out as water.
In tests done in the laboratory, the aerogel gave water non-stop for months.
“Given that atmospheric water is continuously replenished by the global hydrological cycle, our invention offers a promising solution for achieving sustainable freshwater production in a variety of climatic conditions, at minimal energy cost.”
The next step for the team is looking for partners in the industry to scale it up for domestic or industrial use.
Another possibility is that it could even be useful in endurance sports or survival kits.
Top images by National University of Singapore