The material can produce water through both solar steam generation and fog collection - two independent processes that normally require two separate devices.

Solar steam generation, on the one hand, works particularly well in coastal areas because it is also suitable for water purification - but during the day rather than at night. In this method, the heat of the sun evaporates water into steam, which can be condensed into drinking water.

Fog collection, on the other hand, is exactly what it sounds like. At night, low-lying clouds along ocean coasts are heavy with water droplets. Devices that can collect and combine these droplets turn fog into drinking water.

Because the two technologies operate in such different conditions, they typically require different materials and equipment. Now, a material developed at the U.S. University of Caltech could combine them into a single device that produces clean water 24 hours a day.

The newly developed membrane is made of tiny spines of hydrogel strung together. "These spines, which we call 'micro-trees,' attract microscopic droplets of water that are suspended in the air," the researchers share. "They then slide down the base of the spine and merge with other droplets to form relatively heavy drops. These eventually converge to form a reservoir of water that can be utilized."