Video: Solar-hydrogel system efficiently extracts water from airS. Himmelstein | March 15, 2019
A new solar-assisted atmospheric water harvester has been engineered at the University of Texas at Austin as a passive system for freshwater production developing areas. Without the need for an external energy supply, the compact unit can provide water sufficient to meet the daily needs of an average household.
Similar systems have been devised and tested, including a device incorporating aluminum-based metal-organic-framework (MOF) materials designed to extract water from arid desert air. This system yields 400 ml of water per day from a kilogram of MOF, while the new harvesting approach provides up to 50 L per day per kg of hydrogel.
The moisture‐absorbent gel composed of water-absorbing polypyrrole chloride and a water-releasing polymeric network of poly N‐isopropylacrylamide, demonstrated efficient water production over a range of relative humidity levels. The material absorbs water from the atmosphere, which is only released after about five minutes of exposure to natural sunlight.
The solar-hydrogel system could potentially replace core components in existing solar-powered water purification systems or other moisture-absorbing technologies.