Rapid 3D Printing of Aerogels with Bioinspired Surface Structures for Solar Steam Generation

Freshwater scarcity is a critical global challenge. Desalination and water purification, particularly through solar steam generation, offer promising solutions by converting seawater and polluted water into freshwater using solar energy. Aerogels doped with reduced graphene oxide (rGO) enhance this process by improving water transport and solar energy absorption. However, conventional aerogels face limitations due to inefficient water transport driven solely by capillary forces. These limitations push for a much needed approach to address water scarcity by incorporating both water transport and solar energy utilization.

 

Researchers at Arizona State University have developed a polyacrylamide (PAAm)-based aerogel having specific design features using a novel production technique which combines a modified continuous liquid interface projection with further post-processing techniques. In initial tests, the aerogel with the highest water transportation efficiency featured surface channels which exhibited exceptional capillary rise capabilities, enabling rapid antigravity water transport (0.8 cm s⁻¹ at the initial stage, 0.45 g within 10 minutes). Additionally, an efficient solar vapor generation device was developed based on this PAAm aerogel, which was uniformly doped with rGO for enhanced solar absorption, achieving a solar vapor generation rate of 2.1 kg m⁻² h⁻¹ under 1 sun irradiation, effectively addressing water scarcity by significantly enhancing both water transport and evaporation performance.

 

This design offers a novel and efficient approach to address water scarcity by improving both water transport and solar energy utilization.