All-natural, Eco-friendly Composite Foam for Highly Efficient Atmospheric Water Harvesting

B. Chen, S. Jing, T. Li
University of Maryland, College Park,
United States

Keywords: atmospheric water harvesting, water supply system, solar-to-thermal conversion

Summary:

Water is vital for life, yet about 10% of the world population lacks access to it. The atmosphere is a ubiquitous and abundant water reservoir, equivalent to 10% of the freshwater in all lakes on earth. Existing absorbent materials for atmospheric water extraction, such as silica gels, zeolites, and metal-organic frameworks, suffer from either low water capture capacity or expensive and hazardous fabrication processes. Here we demonstrate an all-natural, eco-friendly composite foam with high performance in atmospheric water harvesting in both non-arid and arid environments, solely powered by natural sunlight without any other energy input. The foam can absorb water over 670% of its weight from an atmosphere at 90% relative humidity (RH) and quickly release 95% of absorbed water under sunlight irradiation in 1 h. The all-natural composite foam is also eco- friendly and non-toxic, promising a feasible and efficient green solution to atmospheric water harvesting.