Back in 2017, I wrote about MOF, a porous, metal-organic framework that could be used to capture moisture from desert air. In 2025, that invention was recognized by the Nobel Committee, with Omar Yaghi, a pioneer in reticular chemistry, along with his colleagues Susumu Kitagawa and Richard Robson, receiving the prize for advancements in chemistry. Reticular chemistry involves stitching molecular building blocks into crystalline, extended structures using strong bonds. It is a field of chemistry which appears to be one that Yaghi has invented.
What is a MOF and how does it work?
MOF resembles a sponge made from a nanoscale-pored metal-organic material. Contained within a cartridge, it can be used to adsorb water vapour from ambient air. The process is passive and efficient. The MOF water harvester includes the spongy cartridge contained within an insulated condenser. Overnight or in cooler air, the MOF adsorbs water vapour. When exposed to sunlight, photothermal conversion occurs to raise the MOF’s internal temperature to 65°C (149°F) or higher, releasing the water vapour which contacts the condenser to form water droplets. These are then collected in a reservoir. Used daily, the MOF cartridge can produce water repeatedly without any need for an external power source.
A kilogram (2.2 pounds) MOF cartridge can harvest up to 400 millilitres (13.5 ounces) of water daily in an environment with a humidity of approximately 20%. A smaller handheld version had produced 285 millilitres (9.65 ounces) of water daily. These amounts seem small, but they add up.
The MOF I wrote about in 2017 was constructed using a zirconium composite. This latest version uses aluminum, almost doubling the MOF’s performance. Using aluminum makes the technology more affordable.
When I first discovered this technology after reading an article appearing in the journal Science, entitled, Water harvesting from air with metal-organic frameworks powered by natural sunlight, Yaghi was building microwave-sized water harvesters like the one seen below that could capture up to 5 litres (5.28 quarts) of water daily. One of the prototypes of these water harvesters is seen in the picture below.
What makes MOF such an effective material for adsorption? A MOF lattice provides an enormous adsorption surface within its pores. Every gram of a MOF lattice creates a 10,000 square metre surface area. Yaghi’s research has produced more than 100,000 types of MOFs containing different properties and suitable for different adsorption applications. Some can capture carbon dioxide (CO2) from the smokestacks of coal-fired power plants. Others in fuel tanks can pack more methane (CH4) into vehicles running on natural gas. Similarly, MOFs can pack more hydrogen into fuel tanks.
When Yaghi first introduced MOFs, very few in the field of chemistry expressed interest in exploring the materials and the technology. Now, with the Nobel Prize in hand, MOFs are about to enjoy considerable interest on the part of countries dealing with freshwater scarcity.
Today, the lack of potable freshwater impacts more than 4.3 billion (2.9 billion from 4 to 6 months annually) living in the Middle East, Australia, Central Asia, India, China, Africa, the Southwest U.S., and Central and South America.
Watch this 2018 video to learn how the technology was developed. Today, dozens of companies are studying MOFs and their applications. Yaghi has gone from being a scientist studying an obscure field in chemistry to being one of the most cited chemists on the planet.
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