IIT Guwahati researchers develop efficient method to harvest drinking water from air

A research team led by Dr. Uttam Manna, Associate Professor, Chemistry department and Centre of Nanotechnology, IIT Guwahati, along with his research scholars Kousik Maji, Avijit Das, and Manideepa Dhar, have published the results of this path-breaking work in the prestigious journal of The Royal Society of Chemistry.

With increasing water scarcity throughout the world, there have been attempts to collect and conserve water through non-traditional means.

Scientists have turned to nature to design ways of water harvesting.

For example, in regions of the world with naturally scanty rainfall, plants and insects have devised ingenious strategies to pull and collect water right out of the air. 

Mimicking this, scientists worldwide are trying to build technologies that can pull out water from thin air, both literally and figuratively.

“Such water-harvesting techniques use the concept of hydrophobicity or water-repelling nature of some materials,” Dr. Manna said.

The research team from IIT Guwahati has used the concept of chemically patterned SLIPS for the first time, to effectively harvest water from moist air.

The researchers produced a patterned hydrophilic SLIP by spraying a sponge-like porous polymeric material on top of a simple A4 printer paper.

Further, chemically modulated hydrophilic spots were associated on the coating prior to lubricating with two distinct types of oils – natural olive oil and synthetic krytox. This surface could harvest water from foggy/water vapour laden air without the need for any cooling arrangement.

“We have produced a highly efficient water harvesting interface where the fog collecting rate is as high as 4400±190 mg/cm2/h,” Dr. Uttam Manna said.