New material provides clean water and electricity using nothing but the Sun

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Our atmosphere holds six times more water than you’ll find in all the rivers on Earth. The dew drops you see on grass and water droplets on a cold juice bottle are evidence of this natural reservoir of water. Despite its ubiquity, 2 billion people on Earth still don’t have access to clean drinking water.

A technique called atmospheric water harvesting (AWH) can allow us to extract some of this freshwater out of the air. But there are various challenges that have prevented us from implementing AWH on a large scale. In order to create an effective and continuous AWH system, scientists need to ensure two things. The first is that the water absorption from the air is fully reversible so that the water can be retrieved for use.

The second is efficient waste heat management. When an AWH system captures water from the air, the condensation of water releases heat. If this excess heat is not processed carefully, it can interfere with the entire process. However, it seems that we are now closer to a solution. Inspired by the structure of plant leaves, a team of researchers in China has created a core-shell structural cellulose nanofiber-based aerogel (called Core-Shell@CNF for short) that promises to overcome these challenges.