Featherweight material tackles global water scarcity

An international team of scientists has created an exceptionally lightweight nanomaterial that can efficiently extract significant amounts of clean drinking water from moisture in the air.

The nanomaterial, a calcium-enhanced graphene oxide aerogel, adsorbs water vapor over three times faster than existing technologies while holding more than three times its own weight in water, according to a release from the University of New South Wales (UNSW) on Monday.

The project, led by the Australian Research Council Center of Excellence for Carbon Science and Innovation (ARC COE-CSI) and including Nobel laureate Prof. Kostya Novoselov from the National University of Singapore, found that introducing calcium ions into graphene oxide produced an unexpected molecular synergy, the release said.

This synergy strengthens hydrogen bonding, enabling significantly higher water adsorption than either component achieves alone – a "1+1>2" effect, researchers explained.

"This stronger than expected hydrogen bonding is one of the reasons for the material's extreme ability to adsorb water," said Ren Xiaojun from UNSW's School of Materials Science and Engineering, the study's first author.

The aerogel's nanoporous structure accelerates water capture and allows low-energy release at just 50 degrees Celsius, making it ideal for water-scarce regions. Researchers added that with 2.2 billion people lacking safe drinking water globally, this technology could tap into Earth's 13 million gigalitre atmospheric reservoir.

"Our technology will have application in any region where we have sufficient humidity but limited access to or availability of clean potable water," said UNSW Associate Professor Rakesh Joshi.

The study, published in the Proceedings of the National Academy of Sciences (PNAS), combined experimental and theoretical approaches, utilizing the Australian National Computational Infrastructure supercomputer in Canberra for advanced simulations, researchers said.

Industry partners are working to scale the technology, developed by a team spanning Australia, China, Japan, Singapore and India.

(Cover via VCG)