INNOVATIVE DEVICE TAPS WATER FROM AIR

MIT Researchers have created a high-tech "bubble wrap" capable of collecting safe drinking water directly from the air — even in Death Valley, the driest desert in North America.

“Here we report an atmospheric water harvesting window (AWHW) featuring a vertical origami hydrogel panel and a window-like solar still. This passive, metre-scale device was tested in Death Valley, producing 57.0–161.5 ml of water a day across a relative humidity range of 21–88%. The device has a lifespan of at least 1 year and delivers safe water with lithium-ion concentrations below 0.06 ppm. Our AWHW sets a benchmark in daily water production and climate adaptability, representing an advance towards practical, scalable, safe and sustainable decentralized water solutions for the most water-stressed regions.”

-- From the Abstract “A metre-scale vertical origami hydrogel panel for atmospheric water harvesting in DeathValley”, Published in Nature Water, June 11, 2025, Chang Liu et al.

To improve access to safe and affordable drinking water,  Massachusetts Institute of Technology engineers are tapping into an unconventional source: the air. The Earth’s atmosphere contains millions of billions of gallons of water in the form of vapor. If this vapor can be efficiently captured and condensed, it could supply clean drinking water in places where traditional water resources are inaccessible.

With that goal in mind, the MIT team has developed and tested a new atmospheric water harvester and shown that it efficiently captures water vapor and produces safe drinking water across a range of relative humidities, including dry desert air.

Interview with lead author Will Chang Liu Assistant Professor in the Department of Mechanical Engineering at the National University of Singapore

By Suzanne Forcese

WT: Please introduce yourself to our viewers giving us a brief bio of your academic career and your specific areas of research. What have been the motivating factors that attracted you to this research?
Please also include your work and collaboration with Dr. Zhao at MIT.

Chang Liu: I am currently an Assistant Professor in the Department of Mechanical Engineering at the National University of Singapore (NUS).

My research focuses on the design and engineering of functional hydrogel materials for energy and sustainability applications, including water harvesting, low-grade energy harvesting, and thermal management.

I conducted my postdoctoral research at MIT, where I worked with Professor Zhao. Water scarcity has long been a key focus at MIT, driving the development of advanced water technologies with global impact.

Through our collaboration with researchers in Morocco, we became acutely aware of the urgent need for efficient, scalable, and cost-effective solutions to address water scarcity, particularly in arid climates and remote, landlocked regions. Our expertise in hydrogel design provided a promising platform to explore atmospheric water harvesting as a sustainable approach.

WT: Your work was recently published in the prestigious Nature Water resulting in much media attention for which WT congratulates your team. Can you tell usplease how /why your research interests led you and the team to embark on this project.

Chang Liu: Our interest in this project was driven by the practical limitations of existing sorbent materials. While many materials demonstrate high water uptake under controlled laboratory conditions, they often fail in extreme or variable field environments. Our team set out to address this challenge by developing a hydrogel-based system that is not only efficient at absorbing water but also structurally stable and field-deployable. This work represents a natural extension of our efforts in fundamental hydrogel material design and a commitment to demonstrating real-world utility through rigorous outdoor testing.

WT:Please tell us about the "water harvester" that the Team developed. What does it look like? How does it work? Where did you test the model? What were the results?

Chang Liu: The device we developed is a vertical, window-sized panel constructed from a black, water-absorbent hydrogel material. It is enclosed in a transparent glass chamber coated with a cooling layer to aid condensation. The hydrogel itself resembles black “bubble wrap,” featuring a patterned array of dome-shaped structures.

We tested this device in Death Valley, California. Under varying humidity levels, the system consistently collected between 57 and 161.5 mL of water per day per device. The system operates on a fully passive one-day cycle, absorbing water at night and releasing it via solar-driven evaporation during the day, without requiring any external power.

WT: What are hydrogels? How has your invention improved on existing known models? Your model has been referred to as a 'bubble wrap' like construction. Please elaborate.

Chang Liu: Hydrogels are hydrophilic polymer networks capable of retaining large amounts of water. In our atmospheric water harvesting window (AWHW), we engineered a super-stable hydrogel panel infused with hygroscopic lithium chloride (LiCl), which maintains both structural and chemical stability under wide-ranging temperature and humidity conditions—from extremely hot and dry to cool and humid environments.

The term “bubble wrap” refers to the origami structure, where flat hydrogel films are transformed into dome-shaped arrays. This configuration increases the surface area for air–hydrogel interaction, significantly enhancing water sorption and desorption kinetics.

Our design enables water uptake at relative humidity as low as 18%, while remaining functional at high humidity levels >90%, making it highly adaptable to diverse climates.

WT: What are the possibilities moving forward? What is the vision?

Chang Liu: Now that we have a validated proof of concept in the form of a meter-scale AWHW, we are working on further improving water harvesting efficiency, reducing production costs, and expanding the deployment range.

Our vision is to develop passive, sustainable, and low-maintenance water harvesting systems for arid and semi-arid regions, with potential applications in agriculture and remote infrastructure.

Due to its reduced land footprint enabled by the vertical configuration, we are also exploring how this technology could be integrated into buildings to provide localized water sources.

WT: Any plans for creating a spin-out start-up venture? Are you open to partnerships?

Chang Liu: We are in the process of filing a patent for our technology and are open to exploring potential spin-out opportunities.

We welcome partnerships with those who share our vision of advancing sustainable solutions to address water scarcity.

Our goal is to translate this innovation from the laboratory into real-world applications with meaningful impact.