Quick answer: MOF water harvesting uses porous crystals to adsorb water vapor from air, then releases that water when the material is warmed. A 2017 Science experiment using MOF-801 reported about 2.8 liters of water per kilogram of material per day at 20% relative humidity, with natural sunlight supplying the heat.
What if you no longer needed a well or a river to get water because the source was all around you all the time?
Omar M. Yaghi, a scientist born in Amman and winner of the 2025 Nobel Prize in Chemistry, helped develop highly porous materials known as metal-organic frameworks (MOFs) that can capture water vapor from dry air.
The official Nobel Prize record confirms that Yaghi was born in Amman, Jordan. He shared the 2025 chemistry prize with Susumu Kitagawa and Richard Robson “for the development of metal-organic frameworks.”
How MOF water harvesting works
These materials act like a sponge at the molecular level; absorbing moisture into their microscopic pores and then using the sun’s heat to release and collect the water. In an experiment published in the journal Science, a device based on MOF-801 was able to collect about 2.8 liters of water per kilogram of material per day at 20% humidity, using sunlight as a heat source.
A metal-organic framework is a crystalline network made from metal-containing nodes connected by organic molecules. The arrangement creates pores with an enormous internal surface area. Chemists can tune the pore size and chemistry so a MOF binds water at a chosen humidity range.
The harvesting cycle has three basic stages:
- Air moves across the MOF and water molecules enter its pores.
- The material holds the vapor while the air remains relatively cool.
- Sunlight or another low-grade heat source warms the MOF, releasing the water into a condenser where it can become liquid.
The MOF is not creating water. It is collecting vapor that is already present in the atmosphere.
What the 2017 Science experiment showed
The peer-reviewed paper, “Water harvesting from air with metal-organic frameworks powered by natural sunlight”, appeared in Science on April 28, 2017. Its abstract reports 2.8 liters of water per kilogram of MOF per day at 20% relative humidity.
That number is a material-normalized result from a research device. It should not be read as a guaranteed output for every machine. Actual production changes with temperature, humidity, airflow, the amount of MOF, cycle time, heat transfer, condenser performance, and the size of the complete device.
The important result was that the system worked at a humidity level where conventional condensation becomes energy intensive. It also used ambient sunlight for regeneration instead of an electrically powered refrigeration cycle.
From a laboratory device to desert field tests
The technology has since evolved, and newer models are now capable of operating in extremely arid desert conditions, with designs aimed at producing larger quantities of water more efficiently. Most importantly, while production depends on humidity, the volume of the material, and the device’s design, this technology opens up a real possibility for harvesting water from the air in remote areas.
A follow-up study, “Practical water production from desert air”, was published in Science Advances in 2018. It tested a next-generation device under desert conditions and moved the work closer to continuous outdoor operation.
Researchers have also developed scalable production methods for water-harvesting materials such as MOF-303. A 2023 Nature Protocols paper describes high-yield manufacturing routes intended to make the material greener and easier to produce at larger scale.
Why low humidity does not mean no water
Relative humidity describes how much water vapor the air holds compared with the maximum it could hold at that temperature. Even at 20% relative humidity, air still contains water molecules. The difficulty is capturing them without spending more energy than the recovered water is worth.
MOFs address that problem through selective adsorption. Their pores can fill sharply within a useful humidity window, then empty when warmed. This gives engineers a way to separate vapor from dry air without cooling the entire air stream below its dew point.
Could MOFs help solve water scarcity?
From invisible vapor in the air to collectable water… one day, this may be part of the solution to the global water crisis.
The strongest early use cases are likely to be places where pipes, wells, or large desalination plants are unavailable. A passive or solar-assisted harvester could support remote homes, field stations, emergency operations, or isolated communities.
MOF water harvesting is not yet a universal replacement for municipal water systems. Cost, material durability, daily climate, device maintenance, condenser efficiency, and manufacturing scale all matter. Water intended for drinking also needs safe collection surfaces, storage, and routine quality testing.
The technology is promising because it expands the list of possible water sources. It turns the atmosphere into a reservoir that can be accessed in places where liquid water is scarce, provided the device is designed for the local climate and the expected demand.
Frequently asked questions
What is MOF water harvesting?
MOF water harvesting is a process that uses porous metal-organic frameworks to adsorb water vapor from air and release it as liquid water after heating and condensation.
How much water did the MOF-801 experiment collect?
The 2017 Science paper reported about 2.8 liters per kilogram of MOF per day at 20% relative humidity. That research figure is normalized by material mass and does not guarantee the same output from every device.
Does the system need electricity?
The 2017 prototype used natural sunlight as its heat source. A practical machine may still use electricity for fans, controls, pumps, or active condensation, depending on its design.
Can MOFs collect water in a desert?
Yes. Laboratory and field studies have shown that selected MOFs can adsorb water at low relative humidity. Output still changes with local temperature, humidity, cycle design, and the amount of sorbent.
Is water harvested from air automatically safe to drink?
No. The water must be protected from contamination during collection and storage, and drinking-water systems need appropriate materials, sanitation, and quality testing.
Source: Science Magazine, “Water harvesting from air with metal-organic frameworks applied to desert ambient conditions.”
Editorial source note: The cited 2017 paper’s published title is “Water harvesting from air with metal-organic frameworks powered by natural sunlight.” It appeared in Science 356(6336), 430-434, DOI 10.1126/science.aam8743.
If this approach reaches reliable, affordable scale, water scarcity maps may one day depend not only on rivers and aquifers, but also on what can be recovered from the air above them.
