Novel Sponge-Based Carbonaceous Hydrogel for a Highly Efficient Interfacial Photothermal-Driven Atmospheric Water...

Area of Science:

• Materials Science
• Renewable Energy
• Environmental Engineering

Background:

• Atmospheric water harvesting (AWH) is crucial for addressing water scarcity.
• Traditional AWH methods often face challenges with efficiency and cost.
• Interfacial photothermal evaporation offers a promising avenue for efficient water generation.

Purpose of the Study:

• To develop a high-performance atmospheric water generator (AWG) using interfacial photothermal evaporation.
• To design and fabricate a novel photothermal conversion material for continuous adsorption-desorption of hygroscopic agents.
• To evaluate the water production capacity, efficiency, and cost-effectiveness of the developed AWG.

Main Methods:

• Fabrication of a 3D carbon-containing sponge hydrogel photothermal material (CB/SA@MF) from melamine foam (MF), carbon black (CB), and sodium alginate (SA).
• Application of interfacial photothermal evaporation technology for continuous adsorption-desorption of liquid hygroscopic agents.
• Design of an A4 configuration device with multistage pore structures and water transport channels.
• Testing of the AWG's water production rate, photothermal conversion efficiency, and water quality over multiple cycles.

Main Results:

• The CB/SA@MF material exhibited a high evaporation rate of 1.90 kg·m^-2·h^-1 and a photothermal conversion efficiency of 85.0%.
• The developed AWG achieved a water production rate of 2.84 kg·m^-2·d^-1.
• The device demonstrated excellent material salt resistance and hygroscopic agent regeneration capabilities.
• The total cost of the AWG was as low as $12, with obtained water quality meeting WHO/GB 5749-2022 standards after 5 cycles.

Conclusions:

• The developed interfacial photothermal-driven AWG is a cost-effective and efficient solution for atmospheric water harvesting.
• The novel sponge-based hydrogel photothermal composite material shows significant potential for sustainable water production.
• This technology offers a viable approach to provide fresh water in arid, remote, and resource-limited areas.