Earth’s atmosphere holds billions of gallons of water vapor. If captured, it could supply clean drinking water to over 2.2 billion people who do not have reliable access. Now, MIT scientists have built a device that can pull water from the air — even in some of the driest places on Earth.
The device consists of a sheet of black hydrogel placed between two window-sized glass panes. Hydrogel acts like a sponge, trapping water inside its tiny fibers. To hold more water, its surface is covered with small dome-shaped bumps, like those in bubble wrap. They swell as they absorb the water vapor.
At night, the device collects water vapor from the air. During the day, a special coating on the glass cools the surface, turning the vapor into liquid water. The water droplets run down the glass and are collected in tubes for drinking.
To see how well it worked, the team tested the device for a week in Death Valley, California. This is the driest place in North America. To their delight, the panel captured between a quarter and two-thirds of a cup of drinking water each day.
The researchers believe the panels could collect even more in places with higher humidity. They estimate that eight panels, each about the size of a door, could make enough water for a family’s daily use. This is better than most other water-collecting systems. More importantly, this device does not need batteries, solar panels, or electricity to work.
The findings, published in Nature Water on June 11, 2025, mark only the start of the project.
"This is just a proof-of-concept design, and there are a lot of things we can optimize," said study leader, Dr. Chang Liu. "For instance, we could have a multipanel design. And we're working on a next generation of the material to improve its intrinsic properties further."
Resources: Livescience.com, eurekalert.org, designboom.com