Researchers at the IMDEA Energy Institute, in collaboration with Complutense University of Madrid, have published a comprehensive review of the latest advances in a promising technology that could help tackle water scarcity: solar-driven atmospheric water harvesting using metal-organic frameworks (MOFs).

Access to safe drinking water remains one of the major global challenges of the 21st century, particularly in arid and semi-arid regions and in areas with limited access to conventional water infrastructure. Unlike established solutions such as desalination, which can be highly energy-intensive, atmospheric water harvesting taps into a resource that is available almost everywhere: moisture in the air.

The technology relies on materials capable of adsorbing water vapour from the atmosphere, including under low-humidity conditions, and subsequently releasing the captured water when heated by sunlight. This makes it possible to produce liquid water using solar energy, without the need for electricity or additional infrastructure.

Why MOFs are particularly promising

MOFs are highly porous materials made from metal ions and organic molecules arranged into molecular-scale frameworks. Their structure provides an exceptionally large internal surface area and highly tunable porosity, meaning they can be specifically designed to capture water molecules efficiently, even when relative humidity is low.

Published in Progress in Materials Science, one of the leading journals in the field of materials science, the review examines the key properties required for an effective water-harvesting material. These include high adsorption capacity at low humidity, rapid release of the captured water, and an efficient ability to convert sunlight into heat through what is known as the photothermal effect.

A roadmap towards real-world applications

Beyond reviewing the current state of the technology, the article provides a roadmap for the future development of atmospheric water harvesting systems. The researchers identify the combinations of properties that offer the greatest potential, while also highlighting the challenges that need to be overcome before the technology can be deployed at scale.

Potential applications range from small household devices to community-scale systems capable of providing water in rural areas, remote locations or camps without access to running water.

Article reference: Arjmandi, M., Khayet, M., Horcajada, P. “A holistic review of MOF-based solar-driven atmospheric water harvesting”. Progress in Materials Science, vol. 158, art. 101648, 2026. DOI: 10.1016/j.pmatsci.2025.101648